xref: /btstack/src/hci.c (revision b54464ca655f93a396209e244911d9f2fcf8e3b3)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define BTSTACK_FILE__ "hci.c"
39 
40 /*
41  *  hci.c
42  *
43  *  Created by Matthias Ringwald on 4/29/09.
44  *
45  */
46 
47 #include "btstack_config.h"
48 
49 
50 #ifdef ENABLE_CLASSIC
51 #ifdef HAVE_EMBEDDED_TICK
52 #include "btstack_run_loop_embedded.h"
53 #endif
54 #endif
55 
56 #ifdef HAVE_PLATFORM_IPHONE_OS
57 #include "../port/ios/src/btstack_control_iphone.h"
58 #endif
59 
60 #ifdef ENABLE_BLE
61 #include "gap.h"
62 #include "ble/le_device_db.h"
63 #endif
64 
65 #include <stdarg.h>
66 #include <string.h>
67 #include <inttypes.h>
68 
69 #include "btstack_debug.h"
70 #include "btstack_event.h"
71 #include "btstack_linked_list.h"
72 #include "btstack_memory.h"
73 #include "bluetooth_company_id.h"
74 #include "bluetooth_data_types.h"
75 #include "gap.h"
76 #include "hci.h"
77 #include "hci_cmd.h"
78 #include "hci_dump.h"
79 #include "ad_parser.h"
80 
81 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
82 #ifndef HCI_HOST_ACL_PACKET_NUM
83 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_NUM"
84 #endif
85 #ifndef HCI_HOST_ACL_PACKET_LEN
86 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_LEN"
87 #endif
88 #ifndef HCI_HOST_SCO_PACKET_NUM
89 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_NUM"
90 #endif
91 #ifndef HCI_HOST_SCO_PACKET_LEN
92 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_LEN"
93 #endif
94 #endif
95 
96 #if defined(ENABLE_SCO_OVER_HCI) && defined(ENABLE_SCO_OVER_PCM)
97 #error "SCO data can either be routed over HCI or over PCM, but not over both. Please only enable ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM."
98 #endif
99 
100 #if defined(ENABLE_SCO_OVER_HCI) && defined(HAVE_SCO_TRANSPORT)
101 #error "SCO data can either be routed over HCI or over PCM, but not over both. Please only enable ENABLE_SCO_OVER_HCI or HAVE_SCO_TRANSPORT."
102 #endif
103 
104 #define HCI_CONNECTION_TIMEOUT_MS 10000
105 
106 #ifndef HCI_RESET_RESEND_TIMEOUT_MS
107 #define HCI_RESET_RESEND_TIMEOUT_MS 200
108 #endif
109 
110 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
111 #ifndef GAP_INQUIRY_MAX_NAME_LEN
112 #define GAP_INQUIRY_MAX_NAME_LEN 32
113 #endif
114 
115 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
116 #define GAP_INQUIRY_DURATION_MIN       0x01
117 #define GAP_INQUIRY_DURATION_MAX       0x30
118 #define GAP_INQUIRY_STATE_IDLE         0x00
119 #define GAP_INQUIRY_STATE_W4_ACTIVE    0x80
120 #define GAP_INQUIRY_STATE_ACTIVE       0x81
121 #define GAP_INQUIRY_STATE_W2_CANCEL    0x82
122 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x83
123 
124 // GAP Remote Name Request
125 #define GAP_REMOTE_NAME_STATE_IDLE 0
126 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
127 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
128 
129 // GAP Pairing
130 #define GAP_PAIRING_STATE_IDLE                       0
131 #define GAP_PAIRING_STATE_SEND_PIN                   1
132 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
133 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
134 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
135 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
136 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
137 
138 
139 // prototypes
140 #ifdef ENABLE_CLASSIC
141 static void hci_update_scan_enable(void);
142 static void hci_emit_discoverable_enabled(uint8_t enabled);
143 static int  hci_local_ssp_activated(void);
144 static int  hci_remote_ssp_supported(hci_con_handle_t con_handle);
145 static bool hci_ssp_supported(hci_connection_t * connection);
146 static void hci_notify_if_sco_can_send_now(void);
147 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
148 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
149 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
150 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
151 static void hci_connection_timestamp(hci_connection_t *connection);
152 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
153 static void gap_inquiry_explode(uint8_t *packet, uint16_t size);
154 #endif
155 
156 static int  hci_power_control_on(void);
157 static void hci_power_control_off(void);
158 static void hci_state_reset(void);
159 static void hci_emit_transport_packet_sent(void);
160 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
161 static void hci_emit_nr_connections_changed(void);
162 static void hci_emit_hci_open_failed(void);
163 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
164 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
165 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
166 static void hci_run(void);
167 static int  hci_is_le_connection(hci_connection_t * connection);
168 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
169 
170 #ifdef ENABLE_CLASSIC
171 static int hci_have_usb_transport(void);
172 #endif
173 
174 #ifdef ENABLE_BLE
175 #ifdef ENABLE_LE_CENTRAL
176 // called from test/ble_client/advertising_data_parser.c
177 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
178 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address);
179 static hci_connection_t * gap_get_outgoing_connection(void);
180 #endif
181 #endif
182 
183 // the STACK is here
184 #ifndef HAVE_MALLOC
185 static hci_stack_t   hci_stack_static;
186 #endif
187 static hci_stack_t * hci_stack = NULL;
188 
189 #ifdef ENABLE_CLASSIC
190 // default name
191 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
192 
193 // test helper
194 static uint8_t disable_l2cap_timeouts = 0;
195 #endif
196 
197 /**
198  * create connection for given address
199  *
200  * @return connection OR NULL, if no memory left
201  */
202 static hci_connection_t * create_connection_for_bd_addr_and_type(const bd_addr_t addr, bd_addr_type_t addr_type){
203     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
204     hci_connection_t * conn = btstack_memory_hci_connection_get();
205     if (!conn) return NULL;
206     bd_addr_copy(conn->address, addr);
207     conn->role = HCI_ROLE_INVALID;
208     conn->address_type = addr_type;
209     conn->con_handle = 0xffff;
210     conn->authentication_flags = AUTH_FLAG_NONE;
211     conn->bonding_flags = 0;
212     conn->requested_security_level = LEVEL_0;
213 #ifdef ENABLE_CLASSIC
214     conn->request_role = HCI_ROLE_INVALID;
215     conn->sniff_subrating_max_latency = 0xffff;
216     conn->qos_service_type = HCI_SERVICE_TYPE_INVALID;
217     conn->link_key_type = INVALID_LINK_KEY;
218     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
219     btstack_run_loop_set_timer_context(&conn->timeout, conn);
220     hci_connection_timestamp(conn);
221 #endif
222     conn->acl_recombination_length = 0;
223     conn->acl_recombination_pos = 0;
224     conn->num_packets_sent = 0;
225 
226     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
227 #ifdef ENABLE_BLE
228     conn->le_phy_update_all_phys = 0xff;
229 #endif
230 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
231     conn->le_max_tx_octets = 27;
232 #endif
233     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
234     return conn;
235 }
236 
237 
238 /**
239  * get le connection parameter range
240 *
241  * @return le connection parameter range struct
242  */
243 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
244     *range = hci_stack->le_connection_parameter_range;
245 }
246 
247 /**
248  * set le connection parameter range
249  *
250  */
251 
252 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
253     hci_stack->le_connection_parameter_range = *range;
254 }
255 
256 /**
257  * @brief Test if connection parameters are inside in existing rage
258  * @param conn_interval_min (unit: 1.25ms)
259  * @param conn_interval_max (unit: 1.25ms)
260  * @param conn_latency
261  * @param supervision_timeout (unit: 10ms)
262  * @returns 1 if included
263  */
264 int gap_connection_parameter_range_included(le_connection_parameter_range_t * existing_range, uint16_t le_conn_interval_min, uint16_t le_conn_interval_max, uint16_t le_conn_latency, uint16_t le_supervision_timeout){
265     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
266     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
267 
268     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
269     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
270 
271     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
272     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
273 
274     return 1;
275 }
276 
277 /**
278  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
279  * @note: default: 1
280  * @param max_peripheral_connections
281  */
282 #ifdef ENABLE_LE_PERIPHERAL
283 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
284     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
285 }
286 #endif
287 
288 /**
289  * get hci connections iterator
290  *
291  * @return hci connections iterator
292  */
293 
294 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
295     btstack_linked_list_iterator_init(it, &hci_stack->connections);
296 }
297 
298 /**
299  * get connection for a given handle
300  *
301  * @return connection OR NULL, if not found
302  */
303 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
304     btstack_linked_list_iterator_t it;
305     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
306     while (btstack_linked_list_iterator_has_next(&it)){
307         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
308         if ( item->con_handle == con_handle ) {
309             return item;
310         }
311     }
312     return NULL;
313 }
314 
315 /**
316  * get connection for given address
317  *
318  * @return connection OR NULL, if not found
319  */
320 hci_connection_t * hci_connection_for_bd_addr_and_type(const bd_addr_t  addr, bd_addr_type_t addr_type){
321     btstack_linked_list_iterator_t it;
322     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
323     while (btstack_linked_list_iterator_has_next(&it)){
324         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
325         if (connection->address_type != addr_type)  continue;
326         if (memcmp(addr, connection->address, 6) != 0) continue;
327         return connection;
328     }
329     return NULL;
330 }
331 
332 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
333     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
334 }
335 
336 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
337     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
338 }
339 
340 #ifdef ENABLE_CLASSIC
341 
342 #ifdef ENABLE_SCO_OVER_HCI
343 static int hci_number_sco_connections(void){
344     int connections = 0;
345     btstack_linked_list_iterator_t it;
346     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
347     while (btstack_linked_list_iterator_has_next(&it)){
348         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
349         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
350         connections++;
351     }
352     return connections;
353 }
354 #endif
355 
356 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
357     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
358 #ifdef HAVE_EMBEDDED_TICK
359     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
360         // connections might be timed out
361         hci_emit_l2cap_check_timeout(connection);
362     }
363 #else
364     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
365         // connections might be timed out
366         hci_emit_l2cap_check_timeout(connection);
367     }
368 #endif
369 }
370 
371 static void hci_connection_timestamp(hci_connection_t *connection){
372 #ifdef HAVE_EMBEDDED_TICK
373     connection->timestamp = btstack_run_loop_embedded_get_ticks();
374 #else
375     connection->timestamp = btstack_run_loop_get_time_ms();
376 #endif
377 }
378 
379 /**
380  * add authentication flags and reset timer
381  * @note: assumes classic connection
382  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
383  */
384 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
385     bd_addr_t addr;
386     reverse_bd_addr(bd_addr, addr);
387     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
388     if (conn) {
389         connectionSetAuthenticationFlags(conn, flags);
390         hci_connection_timestamp(conn);
391     }
392 }
393 
394 static bool hci_pairing_active(hci_connection_t * hci_connection){
395     return (hci_connection->authentication_flags & AUTH_FLAG_PAIRING_ACTIVE_MASK) != 0;
396 }
397 
398 static void hci_pairing_started(hci_connection_t * hci_connection, bool ssp){
399     if (hci_pairing_active(hci_connection)) return;
400     if (ssp){
401         hci_connection->authentication_flags |= AUTH_FLAG_SSP_PAIRING_ACTIVE;
402     } else {
403         hci_connection->authentication_flags |= AUTH_FLAG_LEGACY_PAIRING_ACTIVE;
404     }
405     // if we are initiator, we have sent an HCI Authenticate Request
406     bool initiator = (hci_connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0;
407 
408     log_info("pairing started, ssp %u, initiator %u", (int) ssp, (int) initiator);
409 
410     uint8_t event[12];
411     event[0] = GAP_EVENT_PAIRING_STARTED;
412     event[1] = 10;
413     reverse_bd_addr(hci_connection->address, &event[2]);
414     little_endian_store_16(event, 8, (uint16_t) hci_connection->con_handle);
415     event[10] = (uint8_t) ssp;
416     event[11] = (uint8_t) initiator;
417     hci_emit_event(event, sizeof(event), 1);
418 }
419 
420 static void hci_pairing_complete(hci_connection_t * hci_connection, uint8_t status){
421     if (!hci_pairing_active(hci_connection)) return;
422     hci_connection->authentication_flags &= ~AUTH_FLAG_PAIRING_ACTIVE_MASK;
423     log_info("pairing complete, status %02x", status);
424 
425     uint8_t event[12];
426     event[0] = GAP_EVENT_PAIRING_COMPLETE;
427     event[1] = 9;
428     reverse_bd_addr(hci_connection->address, &event[2]);
429     little_endian_store_16(event, 8, (uint16_t) hci_connection->con_handle);
430     event[10] = status;
431     hci_emit_event(event, sizeof(event), 1);
432 }
433 
434 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
435     hci_connection_t * conn = hci_connection_for_handle(handle);
436     if (!conn) return 0;
437     return (int) hci_pairing_active(conn);
438 }
439 
440 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
441     if (!hci_stack->link_key_db) return;
442     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
443     hci_stack->link_key_db->delete_link_key(addr);
444 }
445 
446 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
447     if (!hci_stack->link_key_db) return;
448     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
449     hci_stack->link_key_db->put_link_key(addr, link_key, type);
450 }
451 
452 bool gap_get_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t * type){
453 	if (!hci_stack->link_key_db) return false;
454 	int result = hci_stack->link_key_db->get_link_key(addr, link_key, type) != 0;
455 	log_info("link key for %s available %u, type %u", bd_addr_to_str(addr), result, (int) *type);
456 	return result;
457 }
458 
459 void gap_delete_all_link_keys(void){
460     bd_addr_t  addr;
461     link_key_t link_key;
462     link_key_type_t type;
463     btstack_link_key_iterator_t it;
464     int ok = gap_link_key_iterator_init(&it);
465     if (!ok) {
466         log_error("could not initialize iterator");
467         return;
468     }
469     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
470         gap_drop_link_key_for_bd_addr(addr);
471     }
472     gap_link_key_iterator_done(&it);
473 }
474 
475 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
476     if (!hci_stack->link_key_db) return 0;
477     if (!hci_stack->link_key_db->iterator_init) return 0;
478     return hci_stack->link_key_db->iterator_init(it);
479 }
480 int gap_link_key_iterator_get_next(btstack_link_key_iterator_t * it, bd_addr_t bd_addr, link_key_t link_key, link_key_type_t * type){
481     if (!hci_stack->link_key_db) return 0;
482     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
483 }
484 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
485     if (!hci_stack->link_key_db) return;
486     hci_stack->link_key_db->iterator_done(it);
487 }
488 #endif
489 
490 static bool hci_is_le_connection_type(bd_addr_type_t address_type){
491     switch (address_type){
492         case BD_ADDR_TYPE_LE_PUBLIC:
493         case BD_ADDR_TYPE_LE_RANDOM:
494         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
495         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
496             return true;
497         default:
498             return false;
499     }
500 }
501 
502 static int hci_is_le_connection(hci_connection_t * connection){
503     return hci_is_le_connection_type(connection->address_type);
504 }
505 
506 /**
507  * count connections
508  */
509 static int nr_hci_connections(void){
510     int count = 0;
511     btstack_linked_item_t *it;
512     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
513         count++;
514     }
515     return count;
516 }
517 
518 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
519 
520     unsigned int num_packets_sent_classic = 0;
521     unsigned int num_packets_sent_le = 0;
522 
523     btstack_linked_item_t *it;
524     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
525         hci_connection_t * connection = (hci_connection_t *) it;
526         if (hci_is_le_connection(connection)){
527             num_packets_sent_le += connection->num_packets_sent;
528         }
529         if (connection->address_type == BD_ADDR_TYPE_ACL){
530             num_packets_sent_classic += connection->num_packets_sent;
531         }
532     }
533     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
534     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
535     int free_slots_le = 0;
536 
537     if (free_slots_classic < 0){
538         log_error("hci_number_free_acl_slots: outgoing classic packets (%u) > total classic packets (%u)", num_packets_sent_classic, hci_stack->acl_packets_total_num);
539         return 0;
540     }
541 
542     if (hci_stack->le_acl_packets_total_num){
543         // if we have LE slots, they are used
544         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
545         if (free_slots_le < 0){
546             log_error("hci_number_free_acl_slots: outgoing le packets (%u) > total le packets (%u)", num_packets_sent_le, hci_stack->le_acl_packets_total_num);
547             return 0;
548         }
549     } else {
550         // otherwise, classic slots are used for LE, too
551         free_slots_classic -= num_packets_sent_le;
552         if (free_slots_classic < 0){
553             log_error("hci_number_free_acl_slots: outgoing classic + le packets (%u + %u) > total packets (%u)", num_packets_sent_classic, num_packets_sent_le, hci_stack->acl_packets_total_num);
554             return 0;
555         }
556     }
557 
558     switch (address_type){
559         case BD_ADDR_TYPE_UNKNOWN:
560             log_error("hci_number_free_acl_slots: unknown address type");
561             return 0;
562 
563         case BD_ADDR_TYPE_ACL:
564             return free_slots_classic;
565 
566         default:
567            if (hci_stack->le_acl_packets_total_num){
568                return free_slots_le;
569            }
570            return free_slots_classic;
571     }
572 }
573 
574 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
575     // get connection type
576     hci_connection_t * connection = hci_connection_for_handle(con_handle);
577     if (!connection){
578         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
579         return 0;
580     }
581     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
582 }
583 
584 #ifdef ENABLE_CLASSIC
585 static int hci_number_free_sco_slots(void){
586     unsigned int num_sco_packets_sent  = 0;
587     btstack_linked_item_t *it;
588     if (hci_stack->synchronous_flow_control_enabled){
589         // explicit flow control
590         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
591             hci_connection_t * connection = (hci_connection_t *) it;
592             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
593             num_sco_packets_sent += connection->num_packets_sent;
594         }
595         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
596             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
597             return 0;
598         }
599         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
600     } else {
601         // implicit flow control -- TODO
602         int num_ready = 0;
603         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
604             hci_connection_t * connection = (hci_connection_t *) it;
605             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
606             if (connection->sco_tx_ready == 0) continue;
607             num_ready++;
608         }
609         return num_ready;
610     }
611 }
612 #endif
613 
614 // only used to send HCI Host Number Completed Packets
615 static int hci_can_send_comand_packet_transport(void){
616     if (hci_stack->hci_packet_buffer_reserved) return 0;
617 
618     // check for async hci transport implementations
619     if (hci_stack->hci_transport->can_send_packet_now){
620         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
621             return 0;
622         }
623     }
624     return 1;
625 }
626 
627 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
628 int hci_can_send_command_packet_now(void){
629     if (hci_can_send_comand_packet_transport() == 0) return 0;
630     return hci_stack->num_cmd_packets > 0u;
631 }
632 
633 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
634     // check for async hci transport implementations
635     if (!hci_stack->hci_transport->can_send_packet_now) return 1;
636     return hci_stack->hci_transport->can_send_packet_now(packet_type);
637 }
638 
639 static int hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
640     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
641     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
642 }
643 
644 int hci_can_send_acl_le_packet_now(void){
645     if (hci_stack->hci_packet_buffer_reserved) return 0;
646     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
647 }
648 
649 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
650     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
651     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
652 }
653 
654 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
655     if (hci_stack->hci_packet_buffer_reserved) return 0;
656     return hci_can_send_prepared_acl_packet_now(con_handle);
657 }
658 
659 #ifdef ENABLE_CLASSIC
660 int hci_can_send_acl_classic_packet_now(void){
661     if (hci_stack->hci_packet_buffer_reserved) return 0;
662     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
663 }
664 
665 int hci_can_send_prepared_sco_packet_now(void){
666     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return 0;
667     if (hci_have_usb_transport()){
668         return hci_stack->sco_can_send_now;
669     } else {
670         return hci_number_free_sco_slots() > 0;
671     }
672 }
673 
674 int hci_can_send_sco_packet_now(void){
675     if (hci_stack->hci_packet_buffer_reserved) return 0;
676     return hci_can_send_prepared_sco_packet_now();
677 }
678 
679 void hci_request_sco_can_send_now_event(void){
680     hci_stack->sco_waiting_for_can_send_now = 1;
681     hci_notify_if_sco_can_send_now();
682 }
683 #endif
684 
685 // used for internal checks in l2cap.c
686 int hci_is_packet_buffer_reserved(void){
687     return hci_stack->hci_packet_buffer_reserved;
688 }
689 
690 // reserves outgoing packet buffer. @returns 1 if successful
691 int hci_reserve_packet_buffer(void){
692     if (hci_stack->hci_packet_buffer_reserved) {
693         log_error("hci_reserve_packet_buffer called but buffer already reserved");
694         return 0;
695     }
696     hci_stack->hci_packet_buffer_reserved = 1;
697     return 1;
698 }
699 
700 void hci_release_packet_buffer(void){
701     hci_stack->hci_packet_buffer_reserved = 0;
702 }
703 
704 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
705 static int hci_transport_synchronous(void){
706     return hci_stack->hci_transport->can_send_packet_now == NULL;
707 }
708 
709 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
710 
711     // log_info("hci_send_acl_packet_fragments  %u/%u (con 0x%04x)", hci_stack->acl_fragmentation_pos, hci_stack->acl_fragmentation_total_size, connection->con_handle);
712 
713     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
714     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
715     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0u)){
716         max_acl_data_packet_length = hci_stack->le_data_packets_length;
717     }
718 
719 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
720     if (hci_is_le_connection(connection) && (connection->le_max_tx_octets < max_acl_data_packet_length)){
721         max_acl_data_packet_length = connection->le_max_tx_octets;
722     }
723 #endif
724 
725     log_debug("hci_send_acl_packet_fragments entered");
726 
727     int err;
728     // multiple packets could be send on a synchronous HCI transport
729     while (true){
730 
731         log_debug("hci_send_acl_packet_fragments loop entered");
732 
733         // get current data
734         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4u;
735         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
736         bool more_fragments = false;
737 
738         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
739         if (current_acl_data_packet_length > max_acl_data_packet_length){
740             more_fragments = true;
741             current_acl_data_packet_length = max_acl_data_packet_length;
742         }
743 
744         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
745         if (acl_header_pos > 0u){
746             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
747             handle_and_flags = (handle_and_flags & 0xcfffu) | (1u << 12u);
748             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
749         }
750 
751         // update header len
752         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2u, current_acl_data_packet_length);
753 
754         // count packet
755         connection->num_packets_sent++;
756         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", (int) more_fragments);
757 
758         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
759         if (more_fragments){
760             // update start of next fragment to send
761             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
762         } else {
763             // done
764             hci_stack->acl_fragmentation_pos = 0;
765             hci_stack->acl_fragmentation_total_size = 0;
766         }
767 
768         // send packet
769         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
770         const int size = current_acl_data_packet_length + 4;
771         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
772         hci_stack->acl_fragmentation_tx_active = 1;
773         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
774 
775         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", (int) more_fragments);
776 
777         // done yet?
778         if (!more_fragments) break;
779 
780         // can send more?
781         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
782     }
783 
784     log_debug("hci_send_acl_packet_fragments loop over");
785 
786     // release buffer now for synchronous transport
787     if (hci_transport_synchronous()){
788         hci_stack->acl_fragmentation_tx_active = 0;
789         hci_release_packet_buffer();
790         hci_emit_transport_packet_sent();
791     }
792 
793     return err;
794 }
795 
796 // pre: caller has reserved the packet buffer
797 int hci_send_acl_packet_buffer(int size){
798 
799     // log_info("hci_send_acl_packet_buffer size %u", size);
800 
801     if (!hci_stack->hci_packet_buffer_reserved) {
802         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
803         return 0;
804     }
805 
806     uint8_t * packet = hci_stack->hci_packet_buffer;
807     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
808 
809     // check for free places on Bluetooth module
810     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
811         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
812         hci_release_packet_buffer();
813         hci_emit_transport_packet_sent();
814         return BTSTACK_ACL_BUFFERS_FULL;
815     }
816 
817     hci_connection_t *connection = hci_connection_for_handle( con_handle);
818     if (!connection) {
819         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
820         hci_release_packet_buffer();
821         hci_emit_transport_packet_sent();
822         return 0;
823     }
824 
825 #ifdef ENABLE_CLASSIC
826     hci_connection_timestamp(connection);
827 #endif
828 
829     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
830 
831     // setup data
832     hci_stack->acl_fragmentation_total_size = size;
833     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
834 
835     return hci_send_acl_packet_fragments(connection);
836 }
837 
838 #ifdef ENABLE_CLASSIC
839 // pre: caller has reserved the packet buffer
840 int hci_send_sco_packet_buffer(int size){
841 
842     // log_info("hci_send_acl_packet_buffer size %u", size);
843 
844     if (!hci_stack->hci_packet_buffer_reserved) {
845         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
846         return 0;
847     }
848 
849     uint8_t * packet = hci_stack->hci_packet_buffer;
850 
851     // skip checks in loopback mode
852     if (!hci_stack->loopback_mode){
853         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
854 
855         // check for free places on Bluetooth module
856         if (!hci_can_send_prepared_sco_packet_now()) {
857             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
858             hci_release_packet_buffer();
859             hci_emit_transport_packet_sent();
860             return BTSTACK_ACL_BUFFERS_FULL;
861         }
862 
863         // track send packet in connection struct
864         hci_connection_t *connection = hci_connection_for_handle( con_handle);
865         if (!connection) {
866             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
867             hci_release_packet_buffer();
868             hci_emit_transport_packet_sent();
869             return 0;
870         }
871 
872         if (hci_have_usb_transport()){
873             // token used
874             hci_stack->sco_can_send_now = 0;
875         } else {
876             if (hci_stack->synchronous_flow_control_enabled){
877                 connection->num_packets_sent++;
878             } else {
879                 connection->sco_tx_ready--;
880             }
881         }
882     }
883 
884     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
885 
886 #ifdef HAVE_SCO_TRANSPORT
887     hci_stack->sco_transport->send_packet(packet, size);
888     hci_release_packet_buffer();
889     hci_emit_transport_packet_sent();
890 
891     return 0;
892 #else
893     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
894     if (hci_transport_synchronous()){
895         hci_release_packet_buffer();
896         hci_emit_transport_packet_sent();
897     }
898 
899     return err;
900 #endif
901 }
902 #endif
903 
904 static void acl_handler(uint8_t *packet, uint16_t size){
905 
906     // get info
907     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
908     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
909     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
910     uint16_t acl_length         = READ_ACL_LENGTH(packet);
911 
912     // ignore non-registered handle
913     if (!conn){
914         log_error("acl_handler called with non-registered handle %u!" , con_handle);
915         return;
916     }
917 
918     // assert packet is complete
919     if ((acl_length + 4u) != size){
920         log_error("acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
921         return;
922     }
923 
924 #ifdef ENABLE_CLASSIC
925     // update idle timestamp
926     hci_connection_timestamp(conn);
927 #endif
928 
929 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
930     hci_stack->host_completed_packets = 1;
931     conn->num_packets_completed++;
932 #endif
933 
934     // handle different packet types
935     switch (acl_flags & 0x03u) {
936 
937         case 0x01: // continuation fragment
938 
939             // sanity checks
940             if (conn->acl_recombination_pos == 0u) {
941                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
942                 return;
943             }
944             if ((conn->acl_recombination_pos + acl_length) > (4u + HCI_ACL_BUFFER_SIZE)){
945                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
946                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
947                 conn->acl_recombination_pos = 0;
948                 return;
949             }
950 
951             // append fragment payload (header already stored)
952             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
953                          &packet[4], acl_length);
954             conn->acl_recombination_pos += acl_length;
955 
956             // forward complete L2CAP packet if complete.
957             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4u + 4u)){ // pos already incl. ACL header
958                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
959                 // reset recombination buffer
960                 conn->acl_recombination_length = 0;
961                 conn->acl_recombination_pos = 0;
962             }
963             break;
964 
965         case 0x02: { // first fragment
966 
967             // sanity check
968             if (conn->acl_recombination_pos) {
969                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
970                 conn->acl_recombination_pos = 0;
971             }
972 
973             // peek into L2CAP packet!
974             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
975 
976             // compare fragment size to L2CAP packet size
977             if (acl_length >= (l2cap_length + 4u)){
978                 // forward fragment as L2CAP packet
979                 hci_emit_acl_packet(packet, acl_length + 4u);
980             } else {
981 
982                 if (acl_length > HCI_ACL_BUFFER_SIZE){
983                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
984                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
985                     return;
986                 }
987 
988                 // store first fragment and tweak acl length for complete package
989                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
990                              packet, acl_length + 4u);
991                 conn->acl_recombination_pos    = acl_length + 4u;
992                 conn->acl_recombination_length = l2cap_length;
993                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2u, l2cap_length +4u);
994             }
995             break;
996 
997         }
998         default:
999             log_error( "acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
1000             return;
1001     }
1002 
1003     // execute main loop
1004     hci_run();
1005 }
1006 
1007 static void hci_shutdown_connection(hci_connection_t *conn){
1008     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
1009 
1010 #ifdef ENABLE_CLASSIC
1011 #if defined(ENABLE_SCO_OVER_HCI) || defined(HAVE_SCO_TRANSPORT)
1012     bd_addr_type_t addr_type = conn->address_type;
1013 #endif
1014 #ifdef HAVE_SCO_TRANSPORT
1015     hci_con_handle_t con_handle = conn->con_handle;
1016 #endif
1017 #endif
1018 
1019     btstack_run_loop_remove_timer(&conn->timeout);
1020 
1021     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1022     btstack_memory_hci_connection_free( conn );
1023 
1024     // now it's gone
1025     hci_emit_nr_connections_changed();
1026 
1027 #ifdef ENABLE_CLASSIC
1028 #ifdef ENABLE_SCO_OVER_HCI
1029     // update SCO
1030     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->hci_transport != NULL) && (hci_stack->hci_transport->set_sco_config != NULL)){
1031         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
1032     }
1033 #endif
1034 #ifdef HAVE_SCO_TRANSPORT
1035     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->sco_transport != NULL)){
1036         hci_stack->sco_transport->close(con_handle);
1037     }
1038 #endif
1039 #endif
1040 }
1041 
1042 #ifdef ENABLE_CLASSIC
1043 
1044 static const uint16_t packet_type_sizes[] = {
1045     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
1046     HCI_ACL_DH1_SIZE, 0, 0, 0,
1047     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
1048     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
1049 };
1050 static const uint8_t  packet_type_feature_requirement_bit[] = {
1051      0, // 3 slot packets
1052      1, // 5 slot packets
1053     25, // EDR 2 mpbs
1054     26, // EDR 3 mbps
1055     39, // 3 slot EDR packts
1056     40, // 5 slot EDR packet
1057 };
1058 static const uint16_t packet_type_feature_packet_mask[] = {
1059     0x0f00, // 3 slot packets
1060     0xf000, // 5 slot packets
1061     0x1102, // EDR 2 mpbs
1062     0x2204, // EDR 3 mbps
1063     0x0300, // 3 slot EDR packts
1064     0x3000, // 5 slot EDR packet
1065 };
1066 
1067 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
1068     // enable packet types based on size
1069     uint16_t packet_types = 0;
1070     unsigned int i;
1071     for (i=0;i<16;i++){
1072         if (packet_type_sizes[i] == 0) continue;
1073         if (packet_type_sizes[i] <= buffer_size){
1074             packet_types |= 1 << i;
1075         }
1076     }
1077     // disable packet types due to missing local supported features
1078     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1079         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1080         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1081         if (feature_set) continue;
1082         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1083         packet_types &= ~packet_type_feature_packet_mask[i];
1084     }
1085     // flip bits for "may not be used"
1086     packet_types ^= 0x3306;
1087     return packet_types;
1088 }
1089 
1090 uint16_t hci_usable_acl_packet_types(void){
1091     return hci_stack->packet_types;
1092 }
1093 #endif
1094 
1095 uint8_t* hci_get_outgoing_packet_buffer(void){
1096     // hci packet buffer is >= acl data packet length
1097     return hci_stack->hci_packet_buffer;
1098 }
1099 
1100 uint16_t hci_max_acl_data_packet_length(void){
1101     return hci_stack->acl_data_packet_length;
1102 }
1103 
1104 #ifdef ENABLE_CLASSIC
1105 int hci_extended_sco_link_supported(void){
1106     // No. 31, byte 3, bit 7
1107     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1108 }
1109 #endif
1110 
1111 int hci_non_flushable_packet_boundary_flag_supported(void){
1112     // No. 54, byte 6, bit 6
1113     return (hci_stack->local_supported_features[6u] & (1u << 6u)) != 0u;
1114 }
1115 
1116 static int gap_ssp_supported(void){
1117     // No. 51, byte 6, bit 3
1118     return (hci_stack->local_supported_features[6u] & (1u << 3u)) != 0u;
1119 }
1120 
1121 static int hci_classic_supported(void){
1122 #ifdef ENABLE_CLASSIC
1123     // No. 37, byte 4, bit 5, = No BR/EDR Support
1124     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1125 #else
1126     return 0;
1127 #endif
1128 }
1129 
1130 static int hci_le_supported(void){
1131 #ifdef ENABLE_BLE
1132     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1133     return (hci_stack->local_supported_features[4u] & (1u << 6u)) != 0u;
1134 #else
1135     return 0;
1136 #endif
1137 }
1138 
1139 #ifdef ENABLE_BLE
1140 
1141 static void hci_get_own_address_for_addr_type(uint8_t own_addr_type, bd_addr_t own_addr){
1142     if (own_addr_type == BD_ADDR_TYPE_LE_PUBLIC){
1143         (void)memcpy(own_addr, hci_stack->local_bd_addr, 6);
1144     } else {
1145         (void)memcpy(own_addr, hci_stack->le_random_address, 6);
1146     }
1147 }
1148 
1149 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1150     *addr_type = hci_stack->le_own_addr_type;
1151     hci_get_own_address_for_addr_type(hci_stack->le_own_addr_type, addr);
1152 }
1153 
1154 #ifdef ENABLE_LE_PERIPHERAL
1155 void gap_le_get_own_advertisements_address(uint8_t * addr_type, bd_addr_t addr){
1156     *addr_type = hci_stack->le_advertisements_own_addr_type;
1157     hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, addr);
1158 };
1159 #endif
1160 
1161 #ifdef ENABLE_LE_CENTRAL
1162 
1163 /**
1164  * @brief Get own addr type and address used for LE connections (Central)
1165  */
1166 void gap_le_get_own_connection_address(uint8_t * addr_type, bd_addr_t addr){
1167     *addr_type = hci_stack->le_connection_own_addr_type;
1168     hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, addr);
1169 }
1170 
1171 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1172 
1173     int offset = 3;
1174     int num_reports = packet[offset];
1175     offset += 1;
1176 
1177     int i;
1178     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1179     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1180     for (i=0; (i<num_reports) && (offset < size);i++){
1181         // sanity checks on data_length:
1182         uint8_t data_length = packet[offset + 8];
1183         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1184         if ((offset + 9u + data_length + 1u) > size)    return;
1185         // setup event
1186         uint8_t event_size = 10u + data_length;
1187         int pos = 0;
1188         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1189         event[pos++] = event_size;
1190         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1191         offset += 8;
1192         pos += 8;
1193         event[pos++] = packet[offset + 1 + data_length]; // rssi
1194         event[pos++] = data_length;
1195         offset++;
1196         (void)memcpy(&event[pos], &packet[offset], data_length);
1197         pos +=    data_length;
1198         offset += data_length + 1u; // rssi
1199         hci_emit_event(event, pos, 1);
1200     }
1201 }
1202 #endif
1203 #endif
1204 
1205 #ifdef ENABLE_BLE
1206 #ifdef ENABLE_LE_PERIPHERAL
1207 static void hci_update_advertisements_enabled_for_current_roles(void){
1208     if (hci_stack->le_advertisements_enabled){
1209         // get number of active le slave connections
1210         int num_slave_connections = 0;
1211         btstack_linked_list_iterator_t it;
1212         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1213         while (btstack_linked_list_iterator_has_next(&it)){
1214             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1215             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1216             if (con->state != OPEN) continue;
1217             if (con->role  != HCI_ROLE_SLAVE) continue;
1218             if (!hci_is_le_connection(con)) continue;
1219             num_slave_connections++;
1220         }
1221         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1222         hci_stack->le_advertisements_enabled_for_current_roles = num_slave_connections < hci_stack->le_max_number_peripheral_connections;
1223     } else {
1224         hci_stack->le_advertisements_enabled_for_current_roles = false;
1225     }
1226 }
1227 #endif
1228 #endif
1229 
1230 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1231 
1232 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1233     if (!hci_stack->config) return 0;
1234     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1235     // Limit baud rate for Broadcom chipsets to 3 mbps
1236     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1237         baud_rate = 3000000;
1238     }
1239     return baud_rate;
1240 }
1241 
1242 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1243     UNUSED(ds);
1244 
1245     switch (hci_stack->substate){
1246         case HCI_INIT_W4_SEND_RESET:
1247             log_info("Resend HCI Reset");
1248             hci_stack->substate = HCI_INIT_SEND_RESET;
1249             hci_stack->num_cmd_packets = 1;
1250             hci_run();
1251             break;
1252         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1253             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1254             if (hci_stack->hci_transport->reset_link){
1255                 hci_stack->hci_transport->reset_link();
1256             }
1257 
1258             /* fall through */
1259 
1260         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1261             log_info("Resend HCI Reset - CSR Warm Boot");
1262             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1263             hci_stack->num_cmd_packets = 1;
1264             hci_run();
1265             break;
1266         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1267             if (hci_stack->hci_transport->set_baudrate){
1268                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1269                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1270                 hci_stack->hci_transport->set_baudrate(baud_rate);
1271             }
1272             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1273             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1274                 if (hci_stack->hci_transport->reset_link){
1275                     log_info("Link Reset");
1276                     hci_stack->hci_transport->reset_link();
1277                 }
1278                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1279                 hci_run();
1280             }
1281             break;
1282         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1283             // otherwise continue
1284             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1285             hci_send_cmd(&hci_read_local_supported_commands);
1286             break;
1287         default:
1288             break;
1289     }
1290 }
1291 #endif
1292 
1293 static void hci_initializing_next_state(void){
1294     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1295 }
1296 
1297 // assumption: hci_can_send_command_packet_now() == true
1298 static void hci_initializing_run(void){
1299     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1300     switch (hci_stack->substate){
1301         case HCI_INIT_SEND_RESET:
1302             hci_state_reset();
1303 
1304 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1305             // prepare reset if command complete not received in 100ms
1306             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1307             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1308             btstack_run_loop_add_timer(&hci_stack->timeout);
1309 #endif
1310             // send command
1311             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1312             hci_send_cmd(&hci_reset);
1313             break;
1314         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1315             hci_send_cmd(&hci_read_local_version_information);
1316             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1317             break;
1318         case HCI_INIT_SEND_READ_LOCAL_NAME:
1319             hci_send_cmd(&hci_read_local_name);
1320             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1321             break;
1322 
1323 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1324         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1325             hci_state_reset();
1326             // prepare reset if command complete not received in 100ms
1327             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1328             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1329             btstack_run_loop_add_timer(&hci_stack->timeout);
1330             // send command
1331             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1332             hci_send_cmd(&hci_reset);
1333             break;
1334         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1335             hci_state_reset();
1336             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1337             hci_send_cmd(&hci_reset);
1338             break;
1339         case HCI_INIT_SEND_BAUD_CHANGE: {
1340             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1341             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1342             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1343             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1344             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1345             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1346             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1347             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1348                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1349                 btstack_run_loop_add_timer(&hci_stack->timeout);
1350             }
1351             break;
1352         }
1353         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1354             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1355             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1356             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1357             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1358             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1359             break;
1360         }
1361         case HCI_INIT_CUSTOM_INIT:
1362             // Custom initialization
1363             if (hci_stack->chipset && hci_stack->chipset->next_command){
1364                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1365                 bool send_cmd = false;
1366                 switch (hci_stack->chipset_result){
1367                     case BTSTACK_CHIPSET_VALID_COMMAND:
1368                         send_cmd = true;
1369                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1370                         break;
1371                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1372                         send_cmd = true;
1373                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1374                         log_info("CSR Warm Boot");
1375                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1376                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1377                         btstack_run_loop_add_timer(&hci_stack->timeout);
1378                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1379                             && hci_stack->config
1380                             && hci_stack->chipset
1381                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1382                             && hci_stack->hci_transport->set_baudrate
1383                             && hci_transport_uart_get_main_baud_rate()){
1384                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1385                         } else {
1386                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1387                         }
1388                         break;
1389                     default:
1390                         break;
1391                 }
1392 
1393                 if (send_cmd){
1394                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1395                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1396                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1397                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1398                     break;
1399                 }
1400                 log_info("Init script done");
1401 
1402                 // Init script download on Broadcom chipsets causes:
1403                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1404                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1405                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1406 
1407                     // - baud rate to reset, restore UART baud rate if needed
1408                     int need_baud_change = hci_stack->config
1409                         && hci_stack->chipset
1410                         && hci_stack->chipset->set_baudrate_command
1411                         && hci_stack->hci_transport->set_baudrate
1412                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1413                     if (need_baud_change) {
1414                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1415                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1416                         hci_stack->hci_transport->set_baudrate(baud_rate);
1417                     }
1418 
1419                     uint16_t bcm_delay_ms = 300;
1420                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1421                     //   -> Work around: wait here.
1422                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1423                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1424                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1425                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1426                     btstack_run_loop_add_timer(&hci_stack->timeout);
1427                     break;
1428                 }
1429             }
1430             // otherwise continue
1431             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1432             hci_send_cmd(&hci_read_local_supported_commands);
1433             break;
1434         case HCI_INIT_SET_BD_ADDR:
1435             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1436             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1437             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1438             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1439             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1440             break;
1441 #endif
1442 
1443         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1444             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1445             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1446             hci_send_cmd(&hci_read_local_supported_commands);
1447             break;
1448         case HCI_INIT_READ_BD_ADDR:
1449             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1450             hci_send_cmd(&hci_read_bd_addr);
1451             break;
1452         case HCI_INIT_READ_BUFFER_SIZE:
1453             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1454             hci_send_cmd(&hci_read_buffer_size);
1455             break;
1456         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1457             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1458             hci_send_cmd(&hci_read_local_supported_features);
1459             break;
1460 
1461 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1462         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1463             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1464             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1465             break;
1466         case HCI_INIT_HOST_BUFFER_SIZE:
1467             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1468             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1469                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1470             break;
1471 #endif
1472 
1473         case HCI_INIT_SET_EVENT_MASK:
1474             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1475             if (hci_le_supported()){
1476                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x3FFFFFFFU);
1477             } else {
1478                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1479                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x1FFFFFFFU);
1480             }
1481             break;
1482 
1483 #ifdef ENABLE_CLASSIC
1484         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1485             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1486             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1487             break;
1488         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1489             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1490             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1491             break;
1492         case HCI_INIT_WRITE_DEFAULT_LINK_POLICY_SETTING:
1493             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_LINK_POLICY_SETTING;
1494             hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1495             break;
1496         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1497             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1498             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1499             break;
1500         case HCI_INIT_WRITE_LOCAL_NAME: {
1501             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1502             hci_reserve_packet_buffer();
1503             uint8_t * packet = hci_stack->hci_packet_buffer;
1504             // construct HCI Command and send
1505             uint16_t opcode = hci_write_local_name.opcode;
1506             hci_stack->last_cmd_opcode = opcode;
1507             packet[0] = opcode & 0xff;
1508             packet[1] = opcode >> 8;
1509             packet[2] = DEVICE_NAME_LEN;
1510             memset(&packet[3], 0, DEVICE_NAME_LEN);
1511             uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1512             uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1513             // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1514             (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1515             // expand '00:00:00:00:00:00' in name with bd_addr
1516             btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1517             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1518             break;
1519         }
1520         case HCI_INIT_WRITE_EIR_DATA: {
1521             hci_stack->substate = HCI_INIT_W4_WRITE_EIR_DATA;
1522             hci_reserve_packet_buffer();
1523             uint8_t * packet = hci_stack->hci_packet_buffer;
1524             // construct HCI Command in-place and send
1525             uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1526             hci_stack->last_cmd_opcode = opcode;
1527             uint16_t offset = 0;
1528             packet[offset++] = opcode & 0xff;
1529             packet[offset++] = opcode >> 8;
1530             packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1531             packet[offset++] = 0;  // FEC not required
1532             memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1533             if (hci_stack->eir_data){
1534                 // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1535                 ad_context_t context;
1536                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1537                     uint8_t data_type   = ad_iterator_get_data_type(&context);
1538                     uint8_t size        = ad_iterator_get_data_len(&context);
1539                     const uint8_t *data = ad_iterator_get_data(&context);
1540                     // copy item
1541                     packet[offset++] = size + 1;
1542                     packet[offset++] = data_type;
1543                     memcpy(&packet[offset], data, size);
1544                     // update name item
1545                     if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1546                         btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1547                     }
1548                     offset += size;
1549                 }
1550             } else {
1551                 uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1552                 uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1553                 packet[offset++] = bytes_to_copy + 1;
1554                 packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1555                 (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1556                 // expand '00:00:00:00:00:00' in name with bd_addr
1557                 btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1558             }
1559             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1560             break;
1561         }
1562         case HCI_INIT_WRITE_INQUIRY_MODE:
1563             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1564             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1565             break;
1566         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1567             hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1568 			hci_stack->secure_connections_active = true;
1569             hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1570             break;
1571         case HCI_INIT_WRITE_SCAN_ENABLE:
1572             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1573             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1574             break;
1575         // only sent if ENABLE_SCO_OVER_HCI is defined
1576         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1577             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1578             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1579             break;
1580         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1581             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1582             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1583             break;
1584         // only sent if manufacturer is Broadcom and ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM is defined
1585         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1586             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1587 #ifdef ENABLE_SCO_OVER_HCI
1588             log_info("BCM: Route SCO data via HCI transport");
1589             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1590 #endif
1591 #ifdef ENABLE_SCO_OVER_PCM
1592             log_info("BCM: Route SCO data via PCM interface");
1593 #ifdef ENABLE_BCM_PCM_WBS
1594             // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1595             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 2, 0, 1, 1);
1596 #else
1597             // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1598             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 1, 0, 1, 1);
1599 #endif
1600 #endif
1601             break;
1602 #ifdef ENABLE_SCO_OVER_PCM
1603         case HCI_INIT_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1604             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1605             log_info("BCM: Config PCM interface for I2S");
1606 #ifdef ENABLE_BCM_PCM_WBS
1607             // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1608             hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 2);
1609 #else
1610             // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1611             hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 1);
1612 #endif
1613             break;
1614 #endif
1615 #endif
1616 
1617 #ifdef ENABLE_BLE
1618         // LE INIT
1619         case HCI_INIT_LE_READ_BUFFER_SIZE:
1620             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1621             hci_send_cmd(&hci_le_read_buffer_size);
1622             break;
1623         case HCI_INIT_LE_SET_EVENT_MASK:
1624             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1625             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1626             break;
1627         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1628             // LE Supported Host = 1, Simultaneous Host = 0
1629             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1630             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1631             break;
1632 #endif
1633 
1634 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1635         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1636             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1637             hci_send_cmd(&hci_le_read_maximum_data_length);
1638             break;
1639         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1640             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1641             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1642             break;
1643 #endif
1644 
1645 #ifdef ENABLE_LE_CENTRAL
1646         case HCI_INIT_READ_WHITE_LIST_SIZE:
1647             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1648             hci_send_cmd(&hci_le_read_white_list_size);
1649             break;
1650         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1651             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1652             hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window, hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
1653             break;
1654 #endif
1655         default:
1656             return;
1657     }
1658 }
1659 
1660 static void hci_init_done(void){
1661     // done. tell the app
1662     log_info("hci_init_done -> HCI_STATE_WORKING");
1663     hci_stack->state = HCI_STATE_WORKING;
1664     hci_emit_state();
1665     hci_run();
1666 }
1667 
1668 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1669     bool command_completed = false;
1670     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1671         uint16_t opcode = little_endian_read_16(packet,3);
1672         if (opcode == hci_stack->last_cmd_opcode){
1673             command_completed = true;
1674             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1675         } else {
1676             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1677         }
1678     }
1679 
1680     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1681         uint8_t  status = packet[2];
1682         uint16_t opcode = little_endian_read_16(packet,4);
1683         if (opcode == hci_stack->last_cmd_opcode){
1684             if (status){
1685                 command_completed = true;
1686                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1687             } else {
1688                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1689             }
1690         } else {
1691             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1692         }
1693     }
1694 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1695     // Vendor == CSR
1696     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1697         // TODO: track actual command
1698         command_completed = true;
1699     }
1700 
1701     // Vendor == Toshiba
1702     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1703         // TODO: track actual command
1704         command_completed = true;
1705         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1706         hci_stack->num_cmd_packets = 1;
1707     }
1708 #endif
1709 
1710     return command_completed;
1711 }
1712 
1713 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1714 
1715     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1716 
1717     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1718 
1719 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1720 
1721     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1722     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1723     //
1724     // HCI Reset
1725     // Timeout 100 ms
1726     // HCI Reset
1727     // Command Complete Reset
1728     // HCI Read Local Version Information
1729     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1730     // hang...
1731     //
1732     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1733     if (!command_completed
1734             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1735             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1736 
1737         uint16_t opcode = little_endian_read_16(packet,3);
1738         if (opcode == hci_reset.opcode){
1739             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1740             return;
1741         }
1742     }
1743 
1744     // CSR & H5
1745     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1746     if (!command_completed
1747             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1748             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1749 
1750         uint16_t opcode = little_endian_read_16(packet,3);
1751         if (opcode == hci_reset.opcode){
1752             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1753             return;
1754         }
1755     }
1756 
1757     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1758     // fix: Correct substate and behave as command below
1759     if (command_completed){
1760         switch (hci_stack->substate){
1761             case HCI_INIT_SEND_RESET:
1762                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1763                 break;
1764             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1765                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1766                 break;
1767             default:
1768                 break;
1769         }
1770     }
1771 
1772 #endif
1773 
1774     if (!command_completed) return;
1775 
1776     bool need_baud_change = false;
1777     bool need_addr_change = false;
1778 
1779 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1780     need_baud_change = hci_stack->config
1781                         && hci_stack->chipset
1782                         && hci_stack->chipset->set_baudrate_command
1783                         && hci_stack->hci_transport->set_baudrate
1784                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1785 
1786     need_addr_change = hci_stack->custom_bd_addr_set
1787                         && hci_stack->chipset
1788                         && hci_stack->chipset->set_bd_addr_command;
1789 #endif
1790 
1791     switch(hci_stack->substate){
1792 
1793 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1794         case HCI_INIT_SEND_RESET:
1795             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1796             // fix: just correct substate and behave as command below
1797             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1798             btstack_run_loop_remove_timer(&hci_stack->timeout);
1799             break;
1800         case HCI_INIT_W4_SEND_RESET:
1801             btstack_run_loop_remove_timer(&hci_stack->timeout);
1802             break;
1803         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1804             log_info("Received local name, need baud change %d", (int) need_baud_change);
1805             if (need_baud_change){
1806                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1807                 return;
1808             }
1809             // skip baud change
1810             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1811             return;
1812         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1813             // for STLC2500D, baud rate change already happened.
1814             // for others, baud rate gets changed now
1815             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1816                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1817                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1818                 hci_stack->hci_transport->set_baudrate(baud_rate);
1819             }
1820             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1821             return;
1822         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1823             btstack_run_loop_remove_timer(&hci_stack->timeout);
1824             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1825             return;
1826         case HCI_INIT_W4_CUSTOM_INIT:
1827             // repeat custom init
1828             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1829             return;
1830 #else
1831         case HCI_INIT_W4_SEND_RESET:
1832             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1833             return ;
1834 #endif
1835 
1836         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1837             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1838               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1839                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1840                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1841                 return;
1842             }
1843             if (need_addr_change){
1844                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1845                 return;
1846             }
1847             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1848             return;
1849 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1850         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1851             if (need_baud_change){
1852                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1853                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1854                 hci_stack->hci_transport->set_baudrate(baud_rate);
1855             }
1856             if (need_addr_change){
1857                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1858                 return;
1859             }
1860             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1861             return;
1862         case HCI_INIT_W4_SET_BD_ADDR:
1863             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1864             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1865             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1866                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1867                 return;
1868             }
1869             // skipping st warm boot
1870             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1871             return;
1872         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1873             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1874             return;
1875 #endif
1876         case HCI_INIT_W4_READ_BD_ADDR:
1877             // only read buffer size if supported
1878             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1879                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1880                 return;
1881             }
1882             // skipping read buffer size
1883             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1884             return;
1885         case HCI_INIT_W4_SET_EVENT_MASK:
1886             // skip Classic init commands for LE only chipsets
1887             if (!hci_classic_supported()){
1888 #ifdef ENABLE_BLE
1889                 if (hci_le_supported()){
1890                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1891                     return;
1892                 }
1893 #endif
1894                 log_error("Neither BR/EDR nor LE supported");
1895                 hci_init_done();
1896                 return;
1897             }
1898             if (!gap_ssp_supported()){
1899                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1900                 return;
1901             }
1902             break;
1903 #ifdef ENABLE_BLE
1904         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1905             // skip write le host if not supported (e.g. on LE only EM9301)
1906             if (hci_stack->local_supported_commands[0u] & 0x02u) break;
1907             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1908             return;
1909 
1910 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1911         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1912             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1913             if ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u){
1914                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1915                 return;
1916             }
1917             // explicit fall through to reduce repetitions
1918 
1919 #ifdef ENABLE_LE_CENTRAL
1920             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1921 #else
1922             hci_init_done();
1923 #endif
1924             return;
1925 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1926 
1927 #endif  /* ENABLE_BLE */
1928 
1929         case HCI_INIT_W4_WRITE_INQUIRY_MODE:
1930             // skip write secure connections host support if not supported or disabled
1931             if (!hci_stack->secure_connections_enable || (hci_stack->local_supported_commands[1u] & 0x02u) == 0u) {
1932                 hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;
1933                 return;
1934             }
1935             break;
1936 
1937 #ifdef ENABLE_SCO_OVER_HCI
1938         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1939             // skip write synchronous flow control if not supported
1940             if (hci_stack->local_supported_commands[0] & 0x04) break;
1941             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1942 
1943             /* fall through */
1944 
1945         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1946             // skip write default erroneous data reporting if not supported
1947             if (hci_stack->local_supported_commands[0] & 0x08) break;
1948             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1949 
1950             /* fall through */
1951 
1952         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1953             // skip bcm set sco pcm config on non-Broadcom chipsets
1954             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
1955             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1956 
1957             /* fall through */
1958 
1959         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1960             if (!hci_le_supported()){
1961                 // SKIP LE init for Classic only configuration
1962                 hci_init_done();
1963                 return;
1964             }
1965             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1966             break;
1967 
1968 #else /* !ENABLE_SCO_OVER_HCI */
1969 
1970         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1971 #ifdef ENABLE_SCO_OVER_PCM
1972             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) {
1973                 hci_stack->substate = HCI_INIT_BCM_WRITE_SCO_PCM_INT;
1974                 return;
1975             }
1976 #endif
1977             /* fall through */
1978 
1979         case HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1980 #ifdef ENABLE_BLE
1981             if (hci_le_supported()){
1982                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
1983                 return;
1984             }
1985 #endif
1986             // SKIP LE init for Classic only configuration
1987             hci_init_done();
1988             return;
1989 #endif /* ENABLE_SCO_OVER_HCI */
1990 
1991 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
1992 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
1993         // Response to command before init done state -> init done
1994         case (HCI_INIT_DONE-1):
1995             hci_init_done();
1996             return;
1997 #endif
1998 
1999         default:
2000             break;
2001     }
2002     hci_initializing_next_state();
2003 }
2004 
2005 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
2006     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
2007     bd_addr_t bd_address;
2008     (void)memcpy(&bd_address, conn->address, 6);
2009 
2010 #ifdef ENABLE_CLASSIC
2011     // cache needed data
2012     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
2013 #endif
2014 
2015     // connection failed, remove entry
2016     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2017     btstack_memory_hci_connection_free( conn );
2018 
2019 #ifdef ENABLE_CLASSIC
2020     // notify client if dedicated bonding
2021     if (notify_dedicated_bonding_failed){
2022         log_info("hci notify_dedicated_bonding_failed");
2023         hci_emit_dedicated_bonding_result(bd_address, status);
2024     }
2025 
2026     // if authentication error, also delete link key
2027     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
2028         gap_drop_link_key_for_bd_addr(bd_address);
2029     }
2030 #else
2031     UNUSED(status);
2032 #endif
2033 }
2034 
2035 #ifdef ENABLE_CLASSIC
2036 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
2037     // SSP Controller
2038     if (features[6] & (1 << 3)){
2039         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2040     }
2041     // eSCO
2042     if (features[3] & (1<<7)){
2043         conn->remote_supported_features[0] |= 1;
2044     }
2045     // Extended features
2046     if (features[7] & (1<<7)){
2047         conn->remote_supported_features[0] |= 2;
2048     }
2049 }
2050 
2051 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
2052     // SSP Host
2053     if (features[0] & (1 << 0)){
2054         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2055     }
2056     // SC Host
2057     if (features[0] & (1 << 3)){
2058         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
2059     }
2060 }
2061 
2062 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
2063     // SC Controller
2064     if (features[1] & (1 << 0)){
2065         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2066     }
2067 }
2068 
2069 static void hci_handle_remote_features_received(hci_connection_t * conn){
2070     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2071     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
2072     if (conn->bonding_flags & BONDING_DEDICATED){
2073         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2074     }
2075 }
2076 #endif
2077 
2078 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
2079     // handle BT initialization
2080     if (hci_stack->state == HCI_STATE_INITIALIZING) {
2081         hci_initializing_event_handler(packet, size);
2082     }
2083 
2084     // help with BT sleep
2085     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
2086         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
2087         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
2088         hci_initializing_next_state();
2089     }
2090 }
2091 
2092 #ifdef ENABLE_CLASSIC
2093 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
2094     conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2095     conn->encryption_key_size = encryption_key_size;
2096 
2097     if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) != 0) {
2098         conn->requested_security_level = LEVEL_0;
2099         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
2100         return;
2101     }
2102 
2103     // Request Authentication if not already done
2104     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2105     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2106 }
2107 #endif
2108 
2109 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2110     UNUSED(size);
2111 
2112     uint16_t manufacturer;
2113 #ifdef ENABLE_CLASSIC
2114     hci_con_handle_t handle;
2115     hci_connection_t * conn;
2116     uint8_t status;
2117 #endif
2118     // get num cmd packets - limit to 1 to reduce complexity
2119     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2120 
2121     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2122     switch (opcode){
2123         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2124             if (packet[5]) break;
2125             // terminate, name 248 chars
2126             packet[6+248] = 0;
2127             log_info("local name: %s", &packet[6]);
2128             break;
2129         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2130             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2131             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2132                 uint16_t acl_len = little_endian_read_16(packet, 6);
2133                 uint16_t sco_len = packet[8];
2134 
2135                 // determine usable ACL/SCO payload size
2136                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2137                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2138 
2139                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2140                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2141 
2142                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2143                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2144                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2145             }
2146             break;
2147         case HCI_OPCODE_HCI_READ_RSSI:
2148             if (packet[5] == ERROR_CODE_SUCCESS){
2149                 uint8_t event[5];
2150                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2151                 event[1] = 3;
2152                 (void)memcpy(&event[2], &packet[6], 3);
2153                 hci_emit_event(event, sizeof(event), 1);
2154             }
2155             break;
2156 #ifdef ENABLE_BLE
2157         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2158             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2159             hci_stack->le_acl_packets_total_num = packet[8];
2160             // determine usable ACL payload size
2161             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2162                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2163             }
2164             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2165             break;
2166 #endif
2167 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2168         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2169             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2170             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2171             log_info("hci_le_read_maximum_data_length: tx octets %u, tx time %u us", hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
2172             break;
2173 #endif
2174 #ifdef ENABLE_LE_CENTRAL
2175         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2176             hci_stack->le_whitelist_capacity = packet[6];
2177             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2178             break;
2179 #endif
2180         case HCI_OPCODE_HCI_READ_BD_ADDR:
2181             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2182             log_info("Local Address, Status: 0x%02x: Addr: %s", packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
2183 #ifdef ENABLE_CLASSIC
2184             if (hci_stack->link_key_db){
2185                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2186             }
2187 #endif
2188             break;
2189 #ifdef ENABLE_CLASSIC
2190         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2191             hci_emit_discoverable_enabled(hci_stack->discoverable);
2192             break;
2193         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2194             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2195                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2196                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2197                 hci_emit_event(event, sizeof(event), 1);
2198             }
2199             break;
2200 #endif
2201         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2202             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2203 
2204 #ifdef ENABLE_CLASSIC
2205             // determine usable ACL packet types based on host buffer size and supported features
2206             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2207             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2208 #endif
2209             // Classic/LE
2210             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2211             break;
2212         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2213             manufacturer = little_endian_read_16(packet, 10);
2214             // map Cypress to Broadcom
2215             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2216                 log_info("Treat Cypress as Broadcom");
2217                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2218                 little_endian_store_16(packet, 10, manufacturer);
2219             }
2220             hci_stack->manufacturer = manufacturer;
2221             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2222             break;
2223         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2224             hci_stack->local_supported_commands[0] =
2225                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2226                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2227                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2228                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2229                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2230                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2231                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2232                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2233             hci_stack->local_supported_commands[1] =
2234                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2235                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2236                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u) |  // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2237                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x02u) << 2u) |  // bit 11 = Octet 32, bit 1 / Remote OOB Extended Data Request Reply
2238                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x40u) >> 2u);   // bit 12 = Octet 32, bit 6 / Read Local OOB Extended Data command
2239             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2240             break;
2241 #ifdef ENABLE_CLASSIC
2242         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2243             if (packet[5]) return;
2244             hci_stack->synchronous_flow_control_enabled = 1;
2245             break;
2246         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2247             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2248             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2249             conn   = hci_connection_for_handle(handle);
2250             if (conn != NULL) {
2251                 uint8_t key_size = 0;
2252                 if (status == 0){
2253                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2254                     log_info("Handle %04x key Size: %u", handle, key_size);
2255                 } else {
2256                     key_size = 1;
2257                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2258                 }
2259                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2260             }
2261             break;
2262 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2263         case HCI_OPCODE_HCI_READ_LOCAL_OOB_DATA:
2264         case HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA:{
2265             uint8_t event[67];
2266             event[0] = GAP_EVENT_LOCAL_OOB_DATA;
2267             event[1] = 65;
2268             (void)memset(&event[2], 0, 65);
2269             if (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE] == ERROR_CODE_SUCCESS){
2270                 (void)memcpy(&event[3], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 32);
2271                 if (opcode == HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA){
2272                     event[2] = 3;
2273                     (void)memcpy(&event[35], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+33], 32);
2274                 } else {
2275                     event[2] = 1;
2276                 }
2277             }
2278             hci_emit_event(event, sizeof(event), 0);
2279             break;
2280         }
2281 #endif
2282 #endif
2283         default:
2284             break;
2285     }
2286 }
2287 
2288 #ifdef ENABLE_BLE
2289 static void event_handle_le_connection_complete(const uint8_t * packet){
2290 	bd_addr_t addr;
2291 	bd_addr_type_t addr_type;
2292 	hci_connection_t * conn;
2293 
2294 	// Connection management
2295 	reverse_bd_addr(&packet[8], addr);
2296 	addr_type = (bd_addr_type_t)packet[7];
2297 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2298 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2299 
2300 #ifdef ENABLE_LE_CENTRAL
2301 	// handle error: error is reported only to the initiator -> outgoing connection
2302 	if (packet[3]){
2303 
2304 		// handle cancelled outgoing connection
2305 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2306 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2307 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2308 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2309 		    // reset state
2310             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2311             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2312 			// get outgoing connection conn struct for direct connect
2313 			conn = gap_get_outgoing_connection();
2314 		}
2315 
2316 		// outgoing le connection establishment is done
2317 		if (conn){
2318 			// remove entry
2319 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2320 			btstack_memory_hci_connection_free( conn );
2321 		}
2322 		return;
2323 	}
2324 #endif
2325 
2326 	// on success, both hosts receive connection complete event
2327 	if (packet[6] == HCI_ROLE_MASTER){
2328 #ifdef ENABLE_LE_CENTRAL
2329 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2330 		// note: no hci_connection_t object exists yet for connect with whitelist
2331 		if (hci_is_le_connection_type(addr_type)){
2332 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2333 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2334 		}
2335 #endif
2336 	} else {
2337 #ifdef ENABLE_LE_PERIPHERAL
2338 		// if we're slave, it was an incoming connection, advertisements have stopped
2339 		hci_stack->le_advertisements_active = false;
2340 #endif
2341 	}
2342 
2343 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2344 	if (!conn){
2345 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2346 	}
2347 
2348 	// no memory, sorry.
2349 	if (!conn){
2350 		return;
2351 	}
2352 
2353 	conn->state = OPEN;
2354 	conn->role  = packet[6];
2355 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2356 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2357 
2358 #ifdef ENABLE_LE_PERIPHERAL
2359 	if (packet[6] == HCI_ROLE_SLAVE){
2360 		hci_update_advertisements_enabled_for_current_roles();
2361 	}
2362 #endif
2363 
2364     // init unenhanced att bearer mtu
2365     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2366     conn->att_connection.mtu_exchanged = false;
2367 
2368     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2369 
2370 	// restart timer
2371 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2372 	// btstack_run_loop_add_timer(&conn->timeout);
2373 
2374 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2375 
2376 	hci_emit_nr_connections_changed();
2377 }
2378 #endif
2379 
2380 #ifdef ENABLE_CLASSIC
2381 static bool hci_ssp_security_level_possible_for_io_cap(gap_security_level_t level, uint8_t io_cap_local, uint8_t io_cap_remote){
2382     if (io_cap_local == SSP_IO_CAPABILITY_UNKNOWN) return false;
2383     // LEVEL_4 is tested by l2cap
2384     // LEVEL 3 requires MITM protection -> check io capabilities
2385     if (level >= LEVEL_3){
2386         if (io_cap_remote  >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2387         if (io_cap_local   >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2388         if ((io_cap_remote == SSP_IO_CAPABILITY_KEYBOARD_ONLY) && (io_cap_local ==  SSP_IO_CAPABILITY_KEYBOARD_ONLY)) return false;
2389     }
2390     // LEVEL 2 requires SSP, which is a given
2391     return true;
2392 }
2393 
2394 static bool hci_ssp_validate_possible_security_level(bd_addr_t addr){
2395     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2396     if (!conn) return false;
2397     // abort pairing, if requested security level cannot be met
2398     if (hci_ssp_security_level_possible_for_io_cap(conn->requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io)) {
2399         // inlined hci_add_connection_flags_for_flipped_bd_addr
2400         hci_connection_timestamp(conn);
2401         return true;
2402     } else {
2403         log_info("Level %u cannot be reached", conn->requested_security_level);
2404         conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2405         return false;
2406     };
2407 }
2408 
2409 #endif
2410 
2411 static void event_handler(uint8_t *packet, uint16_t size){
2412 
2413     uint16_t event_length = packet[1];
2414 
2415     // assert packet is complete
2416     if (size != (event_length + 2u)){
2417         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2418         return;
2419     }
2420 
2421     bd_addr_type_t addr_type;
2422     hci_con_handle_t handle;
2423     hci_connection_t * conn;
2424     int i;
2425     int create_connection_cmd;
2426 
2427 #ifdef ENABLE_CLASSIC
2428     hci_link_type_t link_type;
2429     bd_addr_t addr;
2430 #endif
2431 
2432     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2433 
2434     switch (hci_event_packet_get_type(packet)) {
2435 
2436         case HCI_EVENT_COMMAND_COMPLETE:
2437             handle_command_complete_event(packet, size);
2438             break;
2439 
2440         case HCI_EVENT_COMMAND_STATUS:
2441             // get num cmd packets - limit to 1 to reduce complexity
2442             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2443 
2444             // check command status to detected failed outgoing connections
2445             create_connection_cmd = 0;
2446 #ifdef ENABLE_CLASSIC
2447             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2448                 create_connection_cmd = 1;
2449             }
2450 #endif
2451 #ifdef ENABLE_LE_CENTRAL
2452             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2453                 create_connection_cmd = 1;
2454             }
2455 #endif
2456             if (create_connection_cmd) {
2457                 uint8_t status = hci_event_command_status_get_status(packet);
2458                 addr_type = hci_stack->outgoing_addr_type;
2459                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2460                 log_info("command status (create connection), status %x, connection %p, addr %s, type %x", status, conn, bd_addr_to_str(hci_stack->outgoing_addr), addr_type);
2461 
2462                 // reset outgoing address info
2463                 memset(hci_stack->outgoing_addr, 0, 6);
2464                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2465 
2466                 // on error
2467                 if (status != ERROR_CODE_SUCCESS){
2468 #ifdef ENABLE_LE_CENTRAL
2469                     if (hci_is_le_connection_type(addr_type)){
2470                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2471                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2472                     }
2473 #endif
2474                     // error => outgoing connection failed
2475                     if (conn != NULL){
2476                         hci_handle_connection_failed(conn, status);
2477                     }
2478                 }
2479             }
2480 
2481 #ifdef ENABLE_CLASSIC
2482             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_inquiry)) {
2483                 uint8_t status = hci_event_command_status_get_status(packet);
2484                 log_info("command status (inquiry), status %x", status);
2485                 if (status == ERROR_CODE_SUCCESS) {
2486                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
2487                 } else {
2488                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2489                 }
2490             }
2491 #endif
2492             break;
2493 
2494         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2495             if (size < 3) return;
2496             uint16_t num_handles = packet[2];
2497             if (size != (3u + num_handles * 4u)) return;
2498             uint16_t offset = 3;
2499             for (i=0; i<num_handles;i++){
2500                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2501                 offset += 2u;
2502                 uint16_t num_packets = little_endian_read_16(packet, offset);
2503                 offset += 2u;
2504 
2505                 conn = hci_connection_for_handle(handle);
2506                 if (!conn){
2507                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2508                     continue;
2509                 }
2510 
2511                 if (conn->num_packets_sent >= num_packets){
2512                     conn->num_packets_sent -= num_packets;
2513                 } else {
2514                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2515                     conn->num_packets_sent = 0;
2516                 }
2517                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2518 
2519 #ifdef ENABLE_CLASSIC
2520                 // For SCO, we do the can_send_now_check here
2521                 hci_notify_if_sco_can_send_now();
2522 #endif
2523             }
2524             break;
2525         }
2526 
2527 #ifdef ENABLE_CLASSIC
2528         case HCI_EVENT_INQUIRY_COMPLETE:
2529             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2530                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2531                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2532                 hci_emit_event(event, sizeof(event), 1);
2533             }
2534             break;
2535         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2536             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2537                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2538             }
2539             break;
2540         case HCI_EVENT_CONNECTION_REQUEST:
2541             reverse_bd_addr(&packet[2], addr);
2542             link_type = (hci_link_type_t) packet[11];
2543             if (hci_stack->gap_classic_accept_callback != NULL){
2544                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
2545                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2546                     bd_addr_copy(hci_stack->decline_addr, addr);
2547                     break;
2548                 }
2549             }
2550 
2551             // TODO: eval COD 8-10
2552             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
2553             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2554             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2555             if (!conn) {
2556                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2557             }
2558             if (!conn) {
2559                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2560                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2561                 bd_addr_copy(hci_stack->decline_addr, addr);
2562                 break;
2563             }
2564             conn->role  = HCI_ROLE_SLAVE;
2565             conn->state = RECEIVED_CONNECTION_REQUEST;
2566             // store info about eSCO
2567             if (link_type == HCI_LINK_TYPE_ESCO){
2568                 conn->remote_supported_features[0] |= 1;
2569             }
2570             hci_run();
2571             break;
2572 
2573         case HCI_EVENT_CONNECTION_COMPLETE:
2574             // Connection management
2575             reverse_bd_addr(&packet[5], addr);
2576             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2577             addr_type = BD_ADDR_TYPE_ACL;
2578             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2579             if (conn) {
2580                 if (!packet[2]){
2581                     conn->state = OPEN;
2582                     conn->con_handle = little_endian_read_16(packet, 3);
2583 
2584                     // queue get remote feature
2585                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2586 
2587                     // queue set supervision timeout if we're master
2588                     if ((hci_stack->link_supervision_timeout != HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT) && (conn->role == HCI_ROLE_MASTER)){
2589                         connectionSetAuthenticationFlags(conn, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
2590                     }
2591 
2592                     // restart timer
2593                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2594                     btstack_run_loop_add_timer(&conn->timeout);
2595 
2596                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2597 
2598                     hci_emit_nr_connections_changed();
2599                 } else {
2600                     // connection failed
2601                     hci_handle_connection_failed(conn, packet[2]);
2602                 }
2603             }
2604             break;
2605 
2606         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2607             reverse_bd_addr(&packet[5], addr);
2608             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2609             if (packet[2]){
2610                 // connection failed
2611                 break;
2612             }
2613             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2614             if (!conn) {
2615                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2616             }
2617             if (!conn) {
2618                 break;
2619             }
2620             conn->state = OPEN;
2621             conn->con_handle = little_endian_read_16(packet, 3);
2622 
2623 #ifdef ENABLE_SCO_OVER_HCI
2624             // update SCO
2625             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2626                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2627             }
2628             // trigger can send now
2629             if (hci_have_usb_transport()){
2630                 hci_stack->sco_can_send_now = 1;
2631             }
2632 #endif
2633 #ifdef HAVE_SCO_TRANSPORT
2634             // configure sco transport
2635             if (hci_stack->sco_transport != NULL){
2636                 sco_format_t sco_format = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? SCO_FORMAT_8_BIT : SCO_FORMAT_16_BIT;
2637                 hci_stack->sco_transport->open(conn->con_handle, sco_format);
2638             }
2639 #endif
2640             break;
2641 
2642         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2643             handle = little_endian_read_16(packet, 3);
2644             conn = hci_connection_for_handle(handle);
2645             if (!conn) break;
2646             if (!packet[2]){
2647                 const uint8_t * features = &packet[5];
2648                 hci_handle_remote_features_page_0(conn, features);
2649 
2650                 // read extended features if possible
2651                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2652                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2653                     break;
2654                 }
2655             }
2656             hci_handle_remote_features_received(conn);
2657             break;
2658 
2659         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2660             handle = little_endian_read_16(packet, 3);
2661             conn = hci_connection_for_handle(handle);
2662             if (!conn) break;
2663             // status = ok, page = 1
2664             if (!packet[2]) {
2665                 uint8_t page_number = packet[5];
2666                 uint8_t maximum_page_number = packet[6];
2667                 const uint8_t * features = &packet[7];
2668                 bool done = false;
2669                 switch (page_number){
2670                     case 1:
2671                         hci_handle_remote_features_page_1(conn, features);
2672                         if (maximum_page_number >= 2){
2673                             // get Secure Connections (Controller) from Page 2 if available
2674                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2675                         } else {
2676                             // otherwise, assume SC (Controller) == SC (Host)
2677                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2678                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2679                             }
2680                             done = true;
2681                         }
2682                         break;
2683                     case 2:
2684                         hci_handle_remote_features_page_2(conn, features);
2685                         done = true;
2686                         break;
2687                     default:
2688                         break;
2689                 }
2690                 if (!done) break;
2691             }
2692             hci_handle_remote_features_received(conn);
2693             break;
2694 
2695         case HCI_EVENT_LINK_KEY_REQUEST:
2696             // request handled by hci_run()
2697             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
2698             break;
2699 
2700         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2701             hci_event_link_key_request_get_bd_addr(packet, addr);
2702             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2703             if (!conn) break;
2704 
2705             hci_pairing_complete(conn, ERROR_CODE_SUCCESS);
2706 
2707             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2708             // Change Connection Encryption keeps link key type
2709             if (link_key_type != CHANGED_COMBINATION_KEY){
2710                 conn->link_key_type = link_key_type;
2711             }
2712             // cache link key. link keys stored in little-endian format for legacy reasons
2713             memcpy(&conn->link_key, &packet[8], 16);
2714 
2715             // only store link key:
2716             // - if bondable enabled
2717             if (hci_stack->bondable == false) break;
2718             // - if security level sufficient
2719             if (gap_security_level_for_link_key_type(link_key_type) < conn->requested_security_level) break;
2720             // - for SSP, also check if remote side requested bonding as well
2721             if (conn->link_key_type != COMBINATION_KEY){
2722                 bool remote_bonding = conn->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2723                 if (!remote_bonding){
2724                     break;
2725                 }
2726             }
2727             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2728             break;
2729         }
2730 
2731         case HCI_EVENT_PIN_CODE_REQUEST:
2732             hci_event_pin_code_request_get_bd_addr(packet, addr);
2733             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2734             if (!conn) break;
2735 
2736             hci_pairing_started(conn, false);
2737             // non-bondable mode: pin code negative reply will be sent (event is not forwarded to app)
2738             if (!hci_stack->bondable){
2739                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2740                 hci_pairing_complete(conn, ERROR_CODE_PAIRING_NOT_ALLOWED);
2741                 hci_run();
2742                 return;
2743             }
2744             break;
2745 
2746         case HCI_EVENT_IO_CAPABILITY_RESPONSE:
2747             hci_event_io_capability_response_get_bd_addr(packet, addr);
2748             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2749             if (!conn) break;
2750 
2751             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE);
2752             hci_pairing_started(conn, true);
2753             conn->io_cap_response_auth_req = hci_event_io_capability_response_get_authentication_requirements(packet);
2754             conn->io_cap_response_io       = hci_event_io_capability_response_get_io_capability(packet);
2755             break;
2756 
2757         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2758             hci_event_io_capability_response_get_bd_addr(packet, addr);
2759             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2760             if (!conn) break;
2761 
2762             hci_pairing_started(conn, true);
2763 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2764             if (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN){
2765                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
2766             } else {
2767                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2768             }
2769 #endif
2770             break;
2771 
2772 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2773         case HCI_EVENT_REMOTE_OOB_DATA_REQUEST:
2774             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2775             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_REMOTE_OOB_DATA_REPLY);
2776             break;
2777 #endif
2778 
2779         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2780             hci_event_user_confirmation_request_get_bd_addr(packet, addr);
2781             if (hci_ssp_validate_possible_security_level(addr) == false) break;
2782             if (!hci_stack->ssp_auto_accept) break;
2783             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
2784             break;
2785 
2786         case HCI_EVENT_USER_PASSKEY_REQUEST:
2787             hci_event_user_passkey_request_get_bd_addr(packet, addr);
2788             if (hci_ssp_validate_possible_security_level(addr) == false) break;
2789             if (!hci_stack->ssp_auto_accept) break;
2790             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
2791             break;
2792 
2793         case HCI_EVENT_MODE_CHANGE:
2794             handle = hci_event_mode_change_get_handle(packet);
2795             conn = hci_connection_for_handle(handle);
2796             if (!conn) break;
2797             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2798             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2799             break;
2800 #endif
2801 
2802         case HCI_EVENT_ENCRYPTION_CHANGE:
2803             handle = hci_event_encryption_change_get_connection_handle(packet);
2804             conn = hci_connection_for_handle(handle);
2805             if (!conn) break;
2806             if (hci_event_encryption_change_get_status(packet) == 0u) {
2807                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2808                 if (encryption_enabled){
2809                     if (hci_is_le_connection(conn)){
2810                         // For LE, we accept connection as encrypted
2811                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2812                     }
2813 #ifdef ENABLE_CLASSIC
2814                     else {
2815 
2816                         // dedicated bonding: send result and disconnect
2817                         if (conn->bonding_flags & BONDING_DEDICATED){
2818                             conn->bonding_flags &= ~BONDING_DEDICATED;
2819                             conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2820                             conn->bonding_status = packet[2];
2821                             break;
2822                         }
2823 
2824                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
2825                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
2826                         bool connected_uses_aes_ccm = encryption_enabled == 2;
2827                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
2828                             log_info("SC during pairing, but only E0 now -> abort");
2829                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2830                             break;
2831                         }
2832 
2833                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
2834                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
2835                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
2836                         } else {
2837                             // if not, pretend everything is perfect
2838                             hci_handle_read_encryption_key_size_complete(conn, 16);
2839                         }
2840                     }
2841 #endif
2842                 } else {
2843                     conn->authentication_flags &= ~AUTH_FLAG_CONNECTION_ENCRYPTED;
2844                 }
2845             }
2846 
2847             break;
2848 
2849 #ifdef ENABLE_CLASSIC
2850         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
2851             handle = hci_event_authentication_complete_get_connection_handle(packet);
2852             conn = hci_connection_for_handle(handle);
2853             if (!conn) break;
2854 
2855             // clear authentication active flag
2856             conn->bonding_flags &= ~BONDING_SENT_AUTHENTICATE_REQUEST;
2857             hci_pairing_complete(conn, hci_event_authentication_complete_get_status(packet));
2858 
2859             // authenticated only if auth status == 0
2860             if (hci_event_authentication_complete_get_status(packet) == 0){
2861                 // authenticated
2862                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
2863 
2864                 // If not already encrypted, start encryption
2865                 if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0){
2866                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2867                     break;
2868                 }
2869             }
2870 
2871             // emit updated security level
2872             conn->requested_security_level = LEVEL_0;
2873             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2874             break;
2875 
2876         case HCI_EVENT_SIMPLE_PAIRING_COMPLETE:
2877             hci_event_simple_pairing_complete_get_bd_addr(packet, addr);
2878             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2879             if (!conn) break;
2880 
2881             hci_pairing_complete(conn, hci_event_simple_pairing_complete_get_status(packet));
2882             break;
2883 #endif
2884 
2885         // HCI_EVENT_DISCONNECTION_COMPLETE
2886         // has been split, to first notify stack before shutting connection down
2887         // see end of function, too.
2888         case HCI_EVENT_DISCONNECTION_COMPLETE:
2889             if (packet[2]) break;   // status != 0
2890             handle = little_endian_read_16(packet, 3);
2891             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
2892             if (hci_stack->acl_fragmentation_total_size > 0u) {
2893                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
2894                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
2895                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
2896                     hci_stack->acl_fragmentation_total_size = 0;
2897                     hci_stack->acl_fragmentation_pos = 0;
2898                     if (release_buffer){
2899                         hci_release_packet_buffer();
2900                     }
2901                 }
2902             }
2903 
2904             conn = hci_connection_for_handle(handle);
2905             if (!conn) break;
2906 #ifdef ENABLE_CLASSIC
2907             // pairing failed if it was ongoing
2908             hci_pairing_complete(conn, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
2909 #endif
2910             // mark connection for shutdown
2911             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
2912 
2913             // emit dedicatd bonding event
2914             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2915                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
2916             }
2917 
2918 #ifdef ENABLE_BLE
2919 #ifdef ENABLE_LE_PERIPHERAL
2920             // re-enable advertisements for le connections if active
2921             if (hci_is_le_connection(conn)){
2922                 hci_update_advertisements_enabled_for_current_roles();
2923             }
2924 #endif
2925 #endif
2926             break;
2927 
2928         case HCI_EVENT_HARDWARE_ERROR:
2929             log_error("Hardware Error: 0x%02x", packet[2]);
2930             if (hci_stack->hardware_error_callback){
2931                 (*hci_stack->hardware_error_callback)(packet[2]);
2932             } else {
2933                 // if no special requests, just reboot stack
2934                 hci_power_control_off();
2935                 hci_power_control_on();
2936             }
2937             break;
2938 
2939 #ifdef ENABLE_CLASSIC
2940         case HCI_EVENT_ROLE_CHANGE:
2941             if (packet[2]) break;   // status != 0
2942             reverse_bd_addr(&packet[3], addr);
2943             addr_type = BD_ADDR_TYPE_ACL;
2944             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2945             if (!conn) break;
2946             conn->role = packet[9];
2947             break;
2948 #endif
2949 
2950         case HCI_EVENT_TRANSPORT_PACKET_SENT:
2951             // release packet buffer only for asynchronous transport and if there are not further fragements
2952             if (hci_transport_synchronous()) {
2953                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
2954                 return; // instead of break: to avoid re-entering hci_run()
2955             }
2956             hci_stack->acl_fragmentation_tx_active = 0;
2957             if (hci_stack->acl_fragmentation_total_size) break;
2958             hci_release_packet_buffer();
2959 
2960             // L2CAP receives this event via the hci_emit_event below
2961 
2962 #ifdef ENABLE_CLASSIC
2963             // For SCO, we do the can_send_now_check here
2964             hci_notify_if_sco_can_send_now();
2965 #endif
2966             break;
2967 
2968 #ifdef ENABLE_CLASSIC
2969         case HCI_EVENT_SCO_CAN_SEND_NOW:
2970             // For SCO, we do the can_send_now_check here
2971             hci_stack->sco_can_send_now = 1;
2972             hci_notify_if_sco_can_send_now();
2973             return;
2974 
2975         // explode inquriy results for easier consumption
2976         case HCI_EVENT_INQUIRY_RESULT:
2977         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
2978         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
2979             gap_inquiry_explode(packet, size);
2980             break;
2981 #endif
2982 
2983 #ifdef ENABLE_BLE
2984         case HCI_EVENT_LE_META:
2985             switch (packet[2]){
2986 #ifdef ENABLE_LE_CENTRAL
2987                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
2988                     // log_info("advertising report received");
2989                     if (!hci_stack->le_scanning_enabled) break;
2990                     le_handle_advertisement_report(packet, size);
2991                     break;
2992 #endif
2993                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
2994 					event_handle_le_connection_complete(packet);
2995                     break;
2996 
2997                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
2998                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
2999                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
3000                     conn = hci_connection_for_handle(handle);
3001                     if (!conn) break;
3002                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
3003                     break;
3004 
3005                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
3006                     // connection
3007                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
3008                     conn = hci_connection_for_handle(handle);
3009                     if (conn) {
3010                         // read arguments
3011                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
3012                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
3013                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
3014                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
3015 
3016                         // validate against current connection parameter range
3017                         le_connection_parameter_range_t existing_range;
3018                         gap_get_connection_parameter_range(&existing_range);
3019                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
3020                         if (update_parameter){
3021                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
3022                             conn->le_conn_interval_min = le_conn_interval_min;
3023                             conn->le_conn_interval_max = le_conn_interval_max;
3024                             conn->le_conn_latency = le_conn_latency;
3025                             conn->le_supervision_timeout = le_supervision_timeout;
3026                         } else {
3027                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
3028                         }
3029                     }
3030                     break;
3031 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
3032                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
3033                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
3034                     conn = hci_connection_for_handle(handle);
3035                     if (conn) {
3036                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
3037                     }
3038                     break;
3039 #endif
3040                 default:
3041                     break;
3042             }
3043             break;
3044 #endif
3045         case HCI_EVENT_VENDOR_SPECIFIC:
3046             // Vendor specific commands often create vendor specific event instead of num completed packets
3047             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
3048             switch (hci_stack->manufacturer){
3049                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
3050                     hci_stack->num_cmd_packets = 1;
3051                     break;
3052                 default:
3053                     break;
3054             }
3055             break;
3056         default:
3057             break;
3058     }
3059 
3060     handle_event_for_current_stack_state(packet, size);
3061 
3062     // notify upper stack
3063 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
3064 
3065     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
3066     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
3067 		handle = little_endian_read_16(packet, 3);
3068 		hci_connection_t * aConn = hci_connection_for_handle(handle);
3069 		// discard connection if app did not trigger a reconnect in the event handler
3070 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
3071 			hci_shutdown_connection(aConn);
3072 		}
3073     }
3074 
3075 	// execute main loop
3076 	hci_run();
3077 }
3078 
3079 #ifdef ENABLE_CLASSIC
3080 
3081 #ifdef ENABLE_SCO_OVER_HCI
3082 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
3083 static void sco_schedule_tx(hci_connection_t * conn);
3084 
3085 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
3086     log_debug("SCO TX Timeout");
3087     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
3088     hci_connection_t * conn = hci_connection_for_handle(con_handle);
3089     if (!conn) return;
3090 
3091     // trigger send
3092     conn->sco_tx_ready = 1;
3093     // extra packet if CVSD but SCO buffer is too short
3094     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
3095         conn->sco_tx_ready++;
3096     }
3097     hci_notify_if_sco_can_send_now();
3098 }
3099 
3100 
3101 #define SCO_TX_AFTER_RX_MS (6)
3102 
3103 static void sco_schedule_tx(hci_connection_t * conn){
3104 
3105     uint32_t now = btstack_run_loop_get_time_ms();
3106     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
3107     int time_delta_ms = sco_tx_ms - now;
3108 
3109     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
3110 
3111     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
3112     btstack_run_loop_set_timer(timer, time_delta_ms);
3113     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
3114     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
3115     btstack_run_loop_add_timer(timer);
3116 }
3117 #endif
3118 
3119 static void sco_handler(uint8_t * packet, uint16_t size){
3120     // lookup connection struct
3121     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
3122     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
3123     if (!conn) return;
3124 
3125 #ifdef ENABLE_SCO_OVER_HCI
3126     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
3127     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
3128         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
3129             packet[2] = 0x3c;
3130             memmove(&packet[3], &packet[23], 63);
3131             size = 63;
3132         }
3133     }
3134 
3135     if (hci_have_usb_transport()){
3136         // Nothing to do
3137     } else {
3138         // log_debug("sco flow %u, handle 0x%04x, packets sent %u, bytes send %u", hci_stack->synchronous_flow_control_enabled, (int) con_handle, conn->num_packets_sent, conn->num_sco_bytes_sent);
3139         if (hci_stack->synchronous_flow_control_enabled == 0){
3140             uint32_t now = btstack_run_loop_get_time_ms();
3141 
3142             if (!conn->sco_rx_valid){
3143                 // ignore first 10 packets
3144                 conn->sco_rx_count++;
3145                 // log_debug("sco rx count %u", conn->sco_rx_count);
3146                 if (conn->sco_rx_count == 10) {
3147                     // use first timestamp as is and pretent it just started
3148                     conn->sco_rx_ms = now;
3149                     conn->sco_rx_valid = 1;
3150                     conn->sco_rx_count = 0;
3151                     sco_schedule_tx(conn);
3152                 }
3153             } else {
3154                 // track expected arrival timme
3155                 conn->sco_rx_count++;
3156                 conn->sco_rx_ms += 7;
3157                 int delta = (int32_t) (now - conn->sco_rx_ms);
3158                 if (delta > 0){
3159                     conn->sco_rx_ms++;
3160                 }
3161                 // log_debug("sco rx %u", conn->sco_rx_ms);
3162                 sco_schedule_tx(conn);
3163             }
3164         }
3165     }
3166 #endif
3167 
3168     // deliver to app
3169     if (hci_stack->sco_packet_handler) {
3170         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
3171     }
3172 
3173 #ifdef HAVE_SCO_TRANSPORT
3174     // We can send one packet for each received packet
3175     conn->sco_tx_ready++;
3176     hci_notify_if_sco_can_send_now();
3177 #endif
3178 
3179 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3180     conn->num_packets_completed++;
3181     hci_stack->host_completed_packets = 1;
3182     hci_run();
3183 #endif
3184 }
3185 #endif
3186 
3187 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
3188     hci_dump_packet(packet_type, 1, packet, size);
3189     switch (packet_type) {
3190         case HCI_EVENT_PACKET:
3191             event_handler(packet, size);
3192             break;
3193         case HCI_ACL_DATA_PACKET:
3194             acl_handler(packet, size);
3195             break;
3196 #ifdef ENABLE_CLASSIC
3197         case HCI_SCO_DATA_PACKET:
3198             sco_handler(packet, size);
3199             break;
3200 #endif
3201         default:
3202             break;
3203     }
3204 }
3205 
3206 /**
3207  * @brief Add event packet handler.
3208  */
3209 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
3210     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3211 }
3212 
3213 
3214 /** Register HCI packet handlers */
3215 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
3216     hci_stack->acl_packet_handler = handler;
3217 }
3218 
3219 #ifdef ENABLE_CLASSIC
3220 /**
3221  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
3222  */
3223 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
3224     hci_stack->sco_packet_handler = handler;
3225 }
3226 #endif
3227 
3228 static void hci_state_reset(void){
3229     // no connections yet
3230     hci_stack->connections = NULL;
3231 
3232     // keep discoverable/connectable as this has been requested by the client(s)
3233     // hci_stack->discoverable = 0;
3234     // hci_stack->connectable = 0;
3235     // hci_stack->bondable = 1;
3236     // hci_stack->own_addr_type = 0;
3237 
3238     // buffer is free
3239     hci_stack->hci_packet_buffer_reserved = 0;
3240 
3241     // no pending cmds
3242     hci_stack->decline_reason = 0;
3243     hci_stack->new_scan_enable_value = 0xff;
3244 
3245     hci_stack->secure_connections_active = false;
3246 
3247 #ifdef ENABLE_CLASSIC
3248     hci_stack->new_page_scan_interval = 0xffff;
3249     hci_stack->new_page_scan_window = 0xffff;
3250     hci_stack->new_page_scan_type = 0xff;
3251     hci_stack->inquiry_lap = GAP_IAC_GENERAL_INQUIRY;
3252 #endif
3253 
3254 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3255     hci_stack->classic_read_local_oob_data = true;
3256 #endif
3257 
3258     // LE
3259 #ifdef ENABLE_BLE
3260     memset(hci_stack->le_random_address, 0, 6);
3261     hci_stack->le_random_address_set = 0;
3262 #endif
3263 #ifdef ENABLE_LE_CENTRAL
3264     hci_stack->le_scanning_active  = false;
3265     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3266     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3267     hci_stack->le_whitelist_capacity = 0;
3268 #endif
3269 #ifdef ENABLE_LE_PERIPHERAL
3270     hci_stack->le_advertisements_active = false;
3271     if ((hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_PARAMS_SET) != 0){
3272         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3273     }
3274     if (hci_stack->le_advertisements_data != NULL){
3275         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3276     }
3277 #endif
3278 }
3279 
3280 #ifdef ENABLE_CLASSIC
3281 /**
3282  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3283  */
3284 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3285     // store and open remote device db
3286     hci_stack->link_key_db = link_key_db;
3287     if (hci_stack->link_key_db) {
3288         hci_stack->link_key_db->open();
3289     }
3290 }
3291 #endif
3292 
3293 void hci_init(const hci_transport_t *transport, const void *config){
3294 
3295 #ifdef HAVE_MALLOC
3296     if (!hci_stack) {
3297         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3298     }
3299 #else
3300     hci_stack = &hci_stack_static;
3301 #endif
3302     memset(hci_stack, 0, sizeof(hci_stack_t));
3303 
3304     // reference to use transport layer implementation
3305     hci_stack->hci_transport = transport;
3306 
3307     // reference to used config
3308     hci_stack->config = config;
3309 
3310     // setup pointer for outgoing packet buffer
3311     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3312 
3313     // max acl payload size defined in config.h
3314     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3315 
3316     // register packet handlers with transport
3317     transport->register_packet_handler(&packet_handler);
3318 
3319     hci_stack->state = HCI_STATE_OFF;
3320 
3321     // class of device
3322     hci_stack->class_of_device = 0x007a020c; // Smartphone
3323 
3324     // bondable by default
3325     hci_stack->bondable = 1;
3326 
3327 #ifdef ENABLE_CLASSIC
3328     // classic name
3329     hci_stack->local_name = default_classic_name;
3330 
3331     // Master slave policy
3332     hci_stack->master_slave_policy = 1;
3333 
3334     // Allow Role Switch
3335     hci_stack->allow_role_switch = 1;
3336 
3337     // Default / minimum security level = 2
3338     hci_stack->gap_security_level = LEVEL_2;
3339 
3340     // Default Security Mode 4
3341     hci_stack->gap_security_mode = GAP_SECURITY_MODE_4;
3342 
3343     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3344     hci_stack->gap_required_encyrption_key_size = 7;
3345 
3346     // Link Supervision Timeout
3347     hci_stack->link_supervision_timeout = HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT;
3348 
3349 #endif
3350 
3351     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3352     hci_stack->ssp_enable = 1;
3353     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3354     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3355     hci_stack->ssp_auto_accept = 1;
3356 
3357     // Secure Connections: enable (requires support from Controller)
3358     hci_stack->secure_connections_enable = true;
3359 
3360     // voice setting - signed 16 bit pcm data with CVSD over the air
3361     hci_stack->sco_voice_setting = 0x60;
3362 
3363 #ifdef ENABLE_LE_CENTRAL
3364     // connection parameter to use for outgoing connections
3365     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3366     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3367     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3368     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3369     hci_stack->le_connection_latency      = 4;         // 4
3370     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3371     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3372     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3373 
3374     // default LE Scanning
3375     hci_stack->le_scan_type     =   0x1; // active
3376     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3377     hci_stack->le_scan_window   =  0x30; //  30 ms
3378 #endif
3379 
3380 #ifdef ENABLE_LE_PERIPHERAL
3381     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3382 #endif
3383 
3384     // connection parameter range used to answer connection parameter update requests in l2cap
3385     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3386     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3387     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3388     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3389     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3390     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3391 
3392     hci_state_reset();
3393 }
3394 
3395 void hci_deinit(void){
3396 #ifdef HAVE_MALLOC
3397     if (hci_stack) {
3398         free(hci_stack);
3399     }
3400 #endif
3401     hci_stack = NULL;
3402 
3403 #ifdef ENABLE_CLASSIC
3404     disable_l2cap_timeouts = 0;
3405 #endif
3406 }
3407 
3408 /**
3409  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3410  */
3411 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3412     hci_stack->chipset = chipset_driver;
3413 
3414     // reset chipset driver - init is also called on power_up
3415     if (hci_stack->chipset && hci_stack->chipset->init){
3416         hci_stack->chipset->init(hci_stack->config);
3417     }
3418 }
3419 
3420 /**
3421  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3422  */
3423 void hci_set_control(const btstack_control_t *hardware_control){
3424     // references to used control implementation
3425     hci_stack->control = hardware_control;
3426     // init with transport config
3427     hardware_control->init(hci_stack->config);
3428 }
3429 
3430 void hci_close(void){
3431 
3432 #ifdef ENABLE_CLASSIC
3433     // close remote device db
3434     if (hci_stack->link_key_db) {
3435         hci_stack->link_key_db->close();
3436     }
3437 #endif
3438 
3439     btstack_linked_list_iterator_t lit;
3440     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3441     while (btstack_linked_list_iterator_has_next(&lit)){
3442         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3443         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3444         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3445         hci_shutdown_connection(connection);
3446     }
3447 
3448     hci_power_control(HCI_POWER_OFF);
3449 
3450 #ifdef HAVE_MALLOC
3451     free(hci_stack);
3452 #endif
3453     hci_stack = NULL;
3454 }
3455 
3456 #ifdef HAVE_SCO_TRANSPORT
3457 void hci_set_sco_transport(const btstack_sco_transport_t *sco_transport){
3458     hci_stack->sco_transport = sco_transport;
3459     sco_transport->register_packet_handler(&packet_handler);
3460 }
3461 #endif
3462 
3463 #ifdef ENABLE_CLASSIC
3464 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3465     // validate ranage and set
3466     if (encryption_key_size < 7)  return;
3467     if (encryption_key_size > 16) return;
3468     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3469 }
3470 
3471 uint8_t gap_set_security_mode(gap_security_mode_t security_mode){
3472     if ((security_mode == GAP_SECURITY_MODE_4) || (security_mode == GAP_SECURITY_MODE_2)){
3473         hci_stack->gap_security_mode = security_mode;
3474         return ERROR_CODE_SUCCESS;
3475     } else {
3476         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3477     }
3478 }
3479 
3480 gap_security_mode_t gap_get_security_mode(void){
3481     return hci_stack->gap_security_mode;
3482 }
3483 
3484 void gap_set_security_level(gap_security_level_t security_level){
3485     hci_stack->gap_security_level = security_level;
3486 }
3487 
3488 gap_security_level_t gap_get_security_level(void){
3489     return hci_stack->gap_security_level;
3490 }
3491 
3492 void gap_set_secure_connections_only_mode(bool enable){
3493     hci_stack->gap_secure_connections_only_mode = enable;
3494 }
3495 
3496 bool gap_get_secure_connections_only_mode(void){
3497     return hci_stack->gap_secure_connections_only_mode;
3498 }
3499 #endif
3500 
3501 #ifdef ENABLE_CLASSIC
3502 void gap_set_class_of_device(uint32_t class_of_device){
3503     hci_stack->class_of_device = class_of_device;
3504 }
3505 
3506 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3507     hci_stack->default_link_policy_settings = default_link_policy_settings;
3508 }
3509 
3510 void gap_set_allow_role_switch(bool allow_role_switch){
3511     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3512 }
3513 
3514 uint8_t hci_get_allow_role_switch(void){
3515     return  hci_stack->allow_role_switch;
3516 }
3517 
3518 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3519     hci_stack->link_supervision_timeout = link_supervision_timeout;
3520 }
3521 
3522 void hci_disable_l2cap_timeout_check(void){
3523     disable_l2cap_timeouts = 1;
3524 }
3525 #endif
3526 
3527 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
3528 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3529 void hci_set_bd_addr(bd_addr_t addr){
3530     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3531     hci_stack->custom_bd_addr_set = 1;
3532 }
3533 #endif
3534 
3535 // State-Module-Driver overview
3536 // state                    module  low-level
3537 // HCI_STATE_OFF             off      close
3538 // HCI_STATE_INITIALIZING,   on       open
3539 // HCI_STATE_WORKING,        on       open
3540 // HCI_STATE_HALTING,        on       open
3541 // HCI_STATE_SLEEPING,    off/sleep   close
3542 // HCI_STATE_FALLING_ASLEEP  on       open
3543 
3544 static int hci_power_control_on(void){
3545 
3546     // power on
3547     int err = 0;
3548     if (hci_stack->control && hci_stack->control->on){
3549         err = (*hci_stack->control->on)();
3550     }
3551     if (err){
3552         log_error( "POWER_ON failed");
3553         hci_emit_hci_open_failed();
3554         return err;
3555     }
3556 
3557     // int chipset driver
3558     if (hci_stack->chipset && hci_stack->chipset->init){
3559         hci_stack->chipset->init(hci_stack->config);
3560     }
3561 
3562     // init transport
3563     if (hci_stack->hci_transport->init){
3564         hci_stack->hci_transport->init(hci_stack->config);
3565     }
3566 
3567     // open transport
3568     err = hci_stack->hci_transport->open();
3569     if (err){
3570         log_error( "HCI_INIT failed, turning Bluetooth off again");
3571         if (hci_stack->control && hci_stack->control->off){
3572             (*hci_stack->control->off)();
3573         }
3574         hci_emit_hci_open_failed();
3575         return err;
3576     }
3577     return 0;
3578 }
3579 
3580 static void hci_power_control_off(void){
3581 
3582     log_info("hci_power_control_off");
3583 
3584     // close low-level device
3585     hci_stack->hci_transport->close();
3586 
3587     log_info("hci_power_control_off - hci_transport closed");
3588 
3589     // power off
3590     if (hci_stack->control && hci_stack->control->off){
3591         (*hci_stack->control->off)();
3592     }
3593 
3594     log_info("hci_power_control_off - control closed");
3595 
3596     hci_stack->state = HCI_STATE_OFF;
3597 }
3598 
3599 static void hci_power_control_sleep(void){
3600 
3601     log_info("hci_power_control_sleep");
3602 
3603 #if 0
3604     // don't close serial port during sleep
3605 
3606     // close low-level device
3607     hci_stack->hci_transport->close(hci_stack->config);
3608 #endif
3609 
3610     // sleep mode
3611     if (hci_stack->control && hci_stack->control->sleep){
3612         (*hci_stack->control->sleep)();
3613     }
3614 
3615     hci_stack->state = HCI_STATE_SLEEPING;
3616 }
3617 
3618 static int hci_power_control_wake(void){
3619 
3620     log_info("hci_power_control_wake");
3621 
3622     // wake on
3623     if (hci_stack->control && hci_stack->control->wake){
3624         (*hci_stack->control->wake)();
3625     }
3626 
3627 #if 0
3628     // open low-level device
3629     int err = hci_stack->hci_transport->open(hci_stack->config);
3630     if (err){
3631         log_error( "HCI_INIT failed, turning Bluetooth off again");
3632         if (hci_stack->control && hci_stack->control->off){
3633             (*hci_stack->control->off)();
3634         }
3635         hci_emit_hci_open_failed();
3636         return err;
3637     }
3638 #endif
3639 
3640     return 0;
3641 }
3642 
3643 static void hci_power_transition_to_initializing(void){
3644     // set up state machine
3645     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3646     hci_stack->hci_packet_buffer_reserved = 0;
3647     hci_stack->state = HCI_STATE_INITIALIZING;
3648     hci_stack->substate = HCI_INIT_SEND_RESET;
3649 }
3650 
3651 // returns error
3652 static int hci_power_control_state_off(HCI_POWER_MODE power_mode){
3653     int err;
3654     switch (power_mode){
3655         case HCI_POWER_ON:
3656             err = hci_power_control_on();
3657             if (err != 0) {
3658                 log_error("hci_power_control_on() error %d", err);
3659                 return err;
3660             }
3661             hci_power_transition_to_initializing();
3662             break;
3663         case HCI_POWER_OFF:
3664             // do nothing
3665             break;
3666         case HCI_POWER_SLEEP:
3667             // do nothing (with SLEEP == OFF)
3668             break;
3669         default:
3670             btstack_assert(false);
3671             break;
3672     }
3673     return ERROR_CODE_SUCCESS;
3674 }
3675 
3676 static int hci_power_control_state_initializing(HCI_POWER_MODE power_mode){
3677     switch (power_mode){
3678         case HCI_POWER_ON:
3679             // do nothing
3680             break;
3681         case HCI_POWER_OFF:
3682             // no connections yet, just turn it off
3683             hci_power_control_off();
3684             break;
3685         case HCI_POWER_SLEEP:
3686             // no connections yet, just turn it off
3687             hci_power_control_sleep();
3688             break;
3689         default:
3690             btstack_assert(false);
3691             break;
3692     }
3693     return ERROR_CODE_SUCCESS;
3694 }
3695 
3696 static int hci_power_control_state_working(HCI_POWER_MODE power_mode) {
3697     switch (power_mode){
3698         case HCI_POWER_ON:
3699             // do nothing
3700             break;
3701         case HCI_POWER_OFF:
3702             // see hci_run
3703             hci_stack->state = HCI_STATE_HALTING;
3704             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3705             break;
3706         case HCI_POWER_SLEEP:
3707             // see hci_run
3708             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3709             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3710             break;
3711         default:
3712             btstack_assert(false);
3713             break;
3714     }
3715     return ERROR_CODE_SUCCESS;
3716 }
3717 
3718 static int hci_power_control_state_halting(HCI_POWER_MODE power_mode) {
3719     switch (power_mode){
3720         case HCI_POWER_ON:
3721             hci_power_transition_to_initializing();
3722             break;
3723         case HCI_POWER_OFF:
3724             // do nothing
3725             break;
3726         case HCI_POWER_SLEEP:
3727             // see hci_run
3728             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3729             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3730             break;
3731         default:
3732             btstack_assert(false);
3733             break;
3734     }
3735     return ERROR_CODE_SUCCESS;
3736 }
3737 
3738 static int hci_power_control_state_falling_asleep(HCI_POWER_MODE power_mode) {
3739     switch (power_mode){
3740         case HCI_POWER_ON:
3741 
3742 #ifdef HAVE_PLATFORM_IPHONE_OS
3743             // nothing to do, if H4 supports power management
3744                     if (btstack_control_iphone_power_management_enabled()){
3745                         hci_stack->state = HCI_STATE_INITIALIZING;
3746                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
3747                         break;
3748                     }
3749 #endif
3750             hci_power_transition_to_initializing();
3751             break;
3752         case HCI_POWER_OFF:
3753             // see hci_run
3754             hci_stack->state = HCI_STATE_HALTING;
3755             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3756             break;
3757         case HCI_POWER_SLEEP:
3758             // do nothing
3759             break;
3760         default:
3761             btstack_assert(false);
3762             break;
3763     }
3764     return ERROR_CODE_SUCCESS;
3765 }
3766 
3767 static int hci_power_control_state_sleeping(HCI_POWER_MODE power_mode) {
3768     int err;
3769     switch (power_mode){
3770         case HCI_POWER_ON:
3771 #ifdef HAVE_PLATFORM_IPHONE_OS
3772             // nothing to do, if H4 supports power management
3773                     if (btstack_control_iphone_power_management_enabled()){
3774                         hci_stack->state = HCI_STATE_INITIALIZING;
3775                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
3776                         hci_update_scan_enable();
3777                         break;
3778                     }
3779 #endif
3780             err = hci_power_control_wake();
3781             if (err) return err;
3782             hci_power_transition_to_initializing();
3783             break;
3784         case HCI_POWER_OFF:
3785             hci_stack->state = HCI_STATE_HALTING;
3786             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3787             break;
3788         case HCI_POWER_SLEEP:
3789             // do nothing
3790             break;
3791         default:
3792             btstack_assert(false);
3793             break;
3794     }
3795     return ERROR_CODE_SUCCESS;
3796 }
3797 
3798 int hci_power_control(HCI_POWER_MODE power_mode){
3799     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3800     int err = 0;
3801     switch (hci_stack->state){
3802         case HCI_STATE_OFF:
3803             err = hci_power_control_state_off(power_mode);
3804             break;
3805         case HCI_STATE_INITIALIZING:
3806             err = hci_power_control_state_initializing(power_mode);
3807             break;
3808         case HCI_STATE_WORKING:
3809             err = hci_power_control_state_working(power_mode);
3810             break;
3811         case HCI_STATE_HALTING:
3812             err = hci_power_control_state_halting(power_mode);
3813             break;
3814         case HCI_STATE_FALLING_ASLEEP:
3815             err = hci_power_control_state_falling_asleep(power_mode);
3816             break;
3817         case HCI_STATE_SLEEPING:
3818             err = hci_power_control_state_sleeping(power_mode);
3819             break;
3820         default:
3821             btstack_assert(false);
3822             break;
3823     }
3824     if (err != 0){
3825         return err;
3826     }
3827 
3828     // create internal event
3829 	hci_emit_state();
3830 
3831 	// trigger next/first action
3832 	hci_run();
3833 
3834     return 0;
3835 }
3836 
3837 
3838 #ifdef ENABLE_CLASSIC
3839 
3840 static void hci_update_scan_enable(void){
3841     // 2 = page scan, 1 = inq scan
3842     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
3843     hci_run();
3844 }
3845 
3846 void gap_discoverable_control(uint8_t enable){
3847     if (enable) enable = 1; // normalize argument
3848 
3849     if (hci_stack->discoverable == enable){
3850         hci_emit_discoverable_enabled(hci_stack->discoverable);
3851         return;
3852     }
3853 
3854     hci_stack->discoverable = enable;
3855     hci_update_scan_enable();
3856 }
3857 
3858 void gap_connectable_control(uint8_t enable){
3859     if (enable) enable = 1; // normalize argument
3860 
3861     // don't emit event
3862     if (hci_stack->connectable == enable) return;
3863 
3864     hci_stack->connectable = enable;
3865     hci_update_scan_enable();
3866 }
3867 #endif
3868 
3869 void gap_local_bd_addr(bd_addr_t address_buffer){
3870     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
3871 }
3872 
3873 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3874 static void hci_host_num_completed_packets(void){
3875 
3876     // create packet manually as arrays are not supported and num_commands should not get reduced
3877     hci_reserve_packet_buffer();
3878     uint8_t * packet = hci_get_outgoing_packet_buffer();
3879 
3880     uint16_t size = 0;
3881     uint16_t num_handles = 0;
3882     packet[size++] = 0x35;
3883     packet[size++] = 0x0c;
3884     size++;  // skip param len
3885     size++;  // skip num handles
3886 
3887     // add { handle, packets } entries
3888     btstack_linked_item_t * it;
3889     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3890         hci_connection_t * connection = (hci_connection_t *) it;
3891         if (connection->num_packets_completed){
3892             little_endian_store_16(packet, size, connection->con_handle);
3893             size += 2;
3894             little_endian_store_16(packet, size, connection->num_packets_completed);
3895             size += 2;
3896             //
3897             num_handles++;
3898             connection->num_packets_completed = 0;
3899         }
3900     }
3901 
3902     packet[2] = size - 3;
3903     packet[3] = num_handles;
3904 
3905     hci_stack->host_completed_packets = 0;
3906 
3907     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3908     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3909 
3910     // release packet buffer for synchronous transport implementations
3911     if (hci_transport_synchronous()){
3912         hci_release_packet_buffer();
3913         hci_emit_transport_packet_sent();
3914     }
3915 }
3916 #endif
3917 
3918 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
3919     UNUSED(ds);
3920     hci_stack->substate = HCI_HALTING_CLOSE;
3921     // allow packet handlers to defer final shutdown
3922     hci_emit_state();
3923     hci_run();
3924 }
3925 
3926 static bool hci_run_acl_fragments(void){
3927     if (hci_stack->acl_fragmentation_total_size > 0u) {
3928         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
3929         hci_connection_t *connection = hci_connection_for_handle(con_handle);
3930         if (connection) {
3931             if (hci_can_send_prepared_acl_packet_now(con_handle)){
3932                 hci_send_acl_packet_fragments(connection);
3933                 return true;
3934             }
3935         } else {
3936             // connection gone -> discard further fragments
3937             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
3938             hci_stack->acl_fragmentation_total_size = 0;
3939             hci_stack->acl_fragmentation_pos = 0;
3940         }
3941     }
3942     return false;
3943 }
3944 
3945 #ifdef ENABLE_CLASSIC
3946 static bool hci_run_general_gap_classic(void){
3947 
3948     // decline incoming connections
3949     if (hci_stack->decline_reason){
3950         uint8_t reason = hci_stack->decline_reason;
3951         hci_stack->decline_reason = 0;
3952         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
3953         return true;
3954     }
3955     // write page scan activity
3956     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_page_scan_interval != 0xffff) && hci_classic_supported()){
3957         hci_send_cmd(&hci_write_page_scan_activity, hci_stack->new_page_scan_interval, hci_stack->new_page_scan_window);
3958         hci_stack->new_page_scan_interval = 0xffff;
3959         hci_stack->new_page_scan_window = 0xffff;
3960         return true;
3961     }
3962     // write page scan type
3963     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_page_scan_type != 0xff) && hci_classic_supported()){
3964         hci_send_cmd(&hci_write_page_scan_type, hci_stack->new_page_scan_type);
3965         hci_stack->new_page_scan_type = 0xff;
3966         return true;
3967     }
3968     // send scan enable
3969     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_scan_enable_value != 0xff) && hci_classic_supported()){
3970         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
3971         hci_stack->new_scan_enable_value = 0xff;
3972         return true;
3973     }
3974     // start/stop inquiry
3975     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
3976         uint8_t duration = hci_stack->inquiry_state;
3977         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_ACTIVE;
3978         hci_send_cmd(&hci_inquiry, hci_stack->inquiry_lap, duration, 0);
3979         return true;
3980     }
3981     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
3982         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
3983         hci_send_cmd(&hci_inquiry_cancel);
3984         return true;
3985     }
3986     // remote name request
3987     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
3988         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
3989         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
3990                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
3991         return true;
3992     }
3993 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3994     // Local OOB data
3995     if ((hci_stack->state == HCI_STATE_WORKING) && hci_stack->classic_read_local_oob_data){
3996         hci_stack->classic_read_local_oob_data = false;
3997         if (hci_stack->local_supported_commands[1] & 0x10u){
3998             hci_send_cmd(&hci_read_local_extended_oob_data);
3999         } else {
4000             hci_send_cmd(&hci_read_local_oob_data);
4001         }
4002     }
4003 #endif
4004     // pairing
4005     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
4006         uint8_t state = hci_stack->gap_pairing_state;
4007         hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4008         uint8_t pin_code[16];
4009         switch (state){
4010             case GAP_PAIRING_STATE_SEND_PIN:
4011                 memset(pin_code, 0, 16);
4012                 memcpy(pin_code, hci_stack->gap_pairing_input.gap_pairing_pin, hci_stack->gap_pairing_pin_len);
4013                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, pin_code);
4014                 break;
4015             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
4016                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
4017                 break;
4018             case GAP_PAIRING_STATE_SEND_PASSKEY:
4019                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
4020                 break;
4021             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
4022                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
4023                 break;
4024             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
4025                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
4026                 break;
4027             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
4028                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
4029                 break;
4030             default:
4031                 break;
4032         }
4033         return true;
4034     }
4035     return false;
4036 }
4037 #endif
4038 
4039 #ifdef ENABLE_BLE
4040 static bool hci_run_general_gap_le(void){
4041 
4042     // advertisements, active scanning, and creating connections requires random address to be set if using private address
4043 
4044     if (hci_stack->state != HCI_STATE_WORKING) return false;
4045     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
4046 
4047 
4048     // Phase 1: collect what to stop
4049 
4050     bool scanning_stop = false;
4051     bool connecting_stop = false;
4052     bool advertising_stop = false;
4053 
4054 #ifndef ENABLE_LE_CENTRAL
4055     UNUSED(scanning_stop);
4056     UNUSED(connecting_stop);
4057 #endif
4058 #ifndef ENABLE_LE_PERIPHERAL
4059     UNUSED(advertising_stop);
4060 #endif
4061 
4062     // check if whitelist needs modification
4063     bool whitelist_modification_pending = false;
4064     btstack_linked_list_iterator_t lit;
4065     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4066     while (btstack_linked_list_iterator_has_next(&lit)){
4067         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4068         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
4069             whitelist_modification_pending = true;
4070             break;
4071         }
4072     }
4073     // check if resolving list needs modification
4074     bool resolving_list_modification_pending = false;
4075 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4076     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
4077 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
4078         resolving_list_modification_pending = true;
4079     }
4080 #endif
4081 
4082 #ifdef ENABLE_LE_CENTRAL
4083     // scanning control
4084     if (hci_stack->le_scanning_active) {
4085         // stop if:
4086         // - parameter change required
4087         // - it's disabled
4088         // - whitelist change required but used for scanning
4089         // - resolving list modified
4090         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
4091         if ((hci_stack->le_scanning_param_update) ||
4092             !hci_stack->le_scanning_enabled ||
4093             scanning_uses_whitelist ||
4094             resolving_list_modification_pending){
4095 
4096             scanning_stop = true;
4097         }
4098     }
4099 #endif
4100 
4101 #ifdef ENABLE_LE_CENTRAL
4102     // connecting control
4103     bool connecting_with_whitelist;
4104     switch (hci_stack->le_connecting_state){
4105         case LE_CONNECTING_DIRECT:
4106         case LE_CONNECTING_WHITELIST:
4107             // stop connecting if:
4108             // - connecting uses white and whitelist modification pending
4109             // - if it got disabled
4110             // - resolving list modified
4111             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
4112             if ((connecting_with_whitelist && whitelist_modification_pending) ||
4113                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
4114                 resolving_list_modification_pending) {
4115 
4116                 connecting_stop = true;
4117             }
4118             break;
4119         default:
4120             break;
4121     }
4122 #endif
4123 
4124 #ifdef ENABLE_LE_PERIPHERAL
4125     // le advertisement control
4126     if (hci_stack->le_advertisements_active){
4127         // stop if:
4128         // - parameter change required
4129         // - it's disabled
4130         // - whitelist change required but used for advertisement filter policy
4131         // - resolving list modified
4132         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy != 0;
4133         bool advertising_change = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS) != 0;
4134         if (advertising_change ||
4135             (hci_stack->le_advertisements_enabled_for_current_roles == 0) ||
4136             (advertising_uses_whitelist & whitelist_modification_pending) ||
4137             resolving_list_modification_pending) {
4138 
4139             advertising_stop = true;
4140         }
4141     }
4142 #endif
4143 
4144 
4145     // Phase 2: stop everything that should be off during modifications
4146 
4147 #ifdef ENABLE_LE_CENTRAL
4148     if (scanning_stop){
4149         hci_stack->le_scanning_active = false;
4150         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
4151         return true;
4152     }
4153 #endif
4154 
4155 #ifdef ENABLE_LE_CENTRAL
4156     if (connecting_stop){
4157         hci_send_cmd(&hci_le_create_connection_cancel);
4158         return true;
4159     }
4160 #endif
4161 
4162 #ifdef ENABLE_LE_PERIPHERAL
4163     if (advertising_stop){
4164         hci_stack->le_advertisements_active = false;
4165         hci_send_cmd(&hci_le_set_advertise_enable, 0);
4166         return true;
4167     }
4168 #endif
4169 
4170     // Phase 3: modify
4171 
4172 #ifdef ENABLE_LE_CENTRAL
4173     if (hci_stack->le_scanning_param_update){
4174         hci_stack->le_scanning_param_update = false;
4175         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
4176                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
4177         return true;
4178     }
4179 #endif
4180 
4181 #ifdef ENABLE_LE_PERIPHERAL
4182     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
4183         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4184         hci_stack->le_advertisements_own_addr_type = hci_stack->le_own_addr_type;
4185         hci_send_cmd(&hci_le_set_advertising_parameters,
4186                      hci_stack->le_advertisements_interval_min,
4187                      hci_stack->le_advertisements_interval_max,
4188                      hci_stack->le_advertisements_type,
4189                      hci_stack->le_advertisements_own_addr_type,
4190                      hci_stack->le_advertisements_direct_address_type,
4191                      hci_stack->le_advertisements_direct_address,
4192                      hci_stack->le_advertisements_channel_map,
4193                      hci_stack->le_advertisements_filter_policy);
4194         return true;
4195     }
4196     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
4197         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4198         uint8_t adv_data_clean[31];
4199         memset(adv_data_clean, 0, sizeof(adv_data_clean));
4200         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
4201                      hci_stack->le_advertisements_data_len);
4202         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
4203         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
4204         return true;
4205     }
4206     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
4207         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4208         uint8_t scan_data_clean[31];
4209         memset(scan_data_clean, 0, sizeof(scan_data_clean));
4210         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
4211                      hci_stack->le_scan_response_data_len);
4212         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
4213         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
4214         return true;
4215     }
4216 #endif
4217 
4218 
4219 #ifdef ENABLE_LE_CENTRAL
4220     // if connect with whitelist was active and is not cancelled yet, wait until next time
4221     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
4222 #endif
4223 
4224     // LE Whitelist Management
4225     if (whitelist_modification_pending){
4226         // add/remove entries
4227         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4228         while (btstack_linked_list_iterator_has_next(&lit)){
4229             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4230 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
4231 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4232 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
4233 				return true;
4234 			}
4235             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
4236 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
4237                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
4238                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
4239                 return true;
4240             }
4241             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
4242 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4243 				btstack_memory_whitelist_entry_free(entry);
4244             }
4245         }
4246     }
4247 
4248 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4249     // LE Resolving List Management
4250     if (resolving_list_supported) {
4251 		uint16_t i;
4252 		switch (hci_stack->le_resolving_list_state) {
4253 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
4254 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
4255 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
4256 				return true;
4257 			case LE_RESOLVING_LIST_READ_SIZE:
4258 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
4259 				hci_send_cmd(&hci_le_read_resolving_list_size);
4260 				return true;
4261 			case LE_RESOLVING_LIST_SEND_CLEAR:
4262 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
4263 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
4264 							  sizeof(hci_stack->le_resolving_list_add_entries));
4265 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
4266 							  sizeof(hci_stack->le_resolving_list_remove_entries));
4267 				hci_send_cmd(&hci_le_clear_resolving_list);
4268 				return true;
4269 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
4270 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4271 					uint8_t offset = i >> 3;
4272 					uint8_t mask = 1 << (i & 7);
4273 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
4274 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
4275 					bd_addr_t peer_identity_addreses;
4276 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4277 					sm_key_t peer_irk;
4278 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4279 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4280 
4281 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
4282 					// trigger whitelist entry 'update' (work around for controller bug)
4283 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4284 					while (btstack_linked_list_iterator_has_next(&lit)) {
4285 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
4286 						if (entry->address_type != peer_identity_addr_type) continue;
4287 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
4288 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
4289 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
4290 					}
4291 #endif
4292 
4293 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
4294 								 peer_identity_addreses);
4295 					return true;
4296 				}
4297 
4298 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
4299 
4300 				/* fall through */
4301 
4302 			case LE_RESOLVING_LIST_ADD_ENTRIES:
4303 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4304 					uint8_t offset = i >> 3;
4305 					uint8_t mask = 1 << (i & 7);
4306 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
4307 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
4308 					bd_addr_t peer_identity_addreses;
4309 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4310 					sm_key_t peer_irk;
4311 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4312 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4313 					const uint8_t *local_irk = gap_get_persistent_irk();
4314 					// command uses format specifier 'P' that stores 16-byte value without flip
4315 					uint8_t local_irk_flipped[16];
4316 					uint8_t peer_irk_flipped[16];
4317 					reverse_128(local_irk, local_irk_flipped);
4318 					reverse_128(peer_irk, peer_irk_flipped);
4319 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
4320 								 peer_irk_flipped, local_irk_flipped);
4321 					return true;
4322 				}
4323 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4324 				break;
4325 
4326 			default:
4327 				break;
4328 		}
4329 	}
4330     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4331 #endif
4332 
4333     // Phase 4: restore state
4334 
4335 #ifdef ENABLE_LE_CENTRAL
4336     // re-start scanning
4337     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
4338         hci_stack->le_scanning_active = true;
4339         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
4340         return true;
4341     }
4342 #endif
4343 
4344 #ifdef ENABLE_LE_CENTRAL
4345     // re-start connecting
4346     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
4347         bd_addr_t null_addr;
4348         memset(null_addr, 0, 6);
4349         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4350         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4351         hci_send_cmd(&hci_le_create_connection,
4352                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
4353                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
4354                      1,         // use whitelist
4355                      0,         // peer address type
4356                      null_addr, // peer bd addr
4357                      hci_stack->le_connection_own_addr_type,   // our addr type:
4358                      hci_stack->le_connection_interval_min,    // conn interval min
4359                      hci_stack->le_connection_interval_max,    // conn interval max
4360                      hci_stack->le_connection_latency,         // conn latency
4361                      hci_stack->le_supervision_timeout,        // conn latency
4362                      hci_stack->le_minimum_ce_length,          // min ce length
4363                      hci_stack->le_maximum_ce_length           // max ce length
4364         );
4365         return true;
4366     }
4367 #endif
4368 
4369 #ifdef ENABLE_LE_PERIPHERAL
4370     // re-start advertising
4371     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4372         // check if advertisements should be enabled given
4373         hci_stack->le_advertisements_active = true;
4374         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_advertisements_own_address);
4375         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4376         return true;
4377     }
4378 #endif
4379 
4380     return false;
4381 }
4382 #endif
4383 
4384 static bool hci_run_general_pending_commands(void){
4385     btstack_linked_item_t * it;
4386     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4387         hci_connection_t * connection = (hci_connection_t *) it;
4388 
4389         switch(connection->state){
4390             case SEND_CREATE_CONNECTION:
4391                 switch(connection->address_type){
4392 #ifdef ENABLE_CLASSIC
4393                     case BD_ADDR_TYPE_ACL:
4394                         log_info("sending hci_create_connection");
4395                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4396                         break;
4397 #endif
4398                     default:
4399 #ifdef ENABLE_BLE
4400 #ifdef ENABLE_LE_CENTRAL
4401                         log_info("sending hci_le_create_connection");
4402                         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4403                         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4404                         hci_send_cmd(&hci_le_create_connection,
4405                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4406                                      hci_stack->le_connection_scan_window,      // conn scan windows
4407                                      0,         // don't use whitelist
4408                                      connection->address_type, // peer address type
4409                                      connection->address,      // peer bd addr
4410                                      hci_stack->le_connection_own_addr_type,   // our addr type:
4411                                      hci_stack->le_connection_interval_min,    // conn interval min
4412                                      hci_stack->le_connection_interval_max,    // conn interval max
4413                                      hci_stack->le_connection_latency,         // conn latency
4414                                      hci_stack->le_supervision_timeout,        // conn latency
4415                                      hci_stack->le_minimum_ce_length,          // min ce length
4416                                      hci_stack->le_maximum_ce_length          // max ce length
4417                         );
4418                         connection->state = SENT_CREATE_CONNECTION;
4419 #endif
4420 #endif
4421                         break;
4422                 }
4423                 return true;
4424 
4425 #ifdef ENABLE_CLASSIC
4426             case RECEIVED_CONNECTION_REQUEST:
4427                 connection->role  = HCI_ROLE_SLAVE;
4428                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4429                     log_info("sending hci_accept_connection_request");
4430                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4431                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4432                 }
4433                 return true;
4434 #endif
4435 
4436 #ifdef ENABLE_BLE
4437 #ifdef ENABLE_LE_CENTRAL
4438             case SEND_CANCEL_CONNECTION:
4439                 connection->state = SENT_CANCEL_CONNECTION;
4440                 hci_send_cmd(&hci_le_create_connection_cancel);
4441                 return true;
4442 #endif
4443 #endif
4444             case SEND_DISCONNECT:
4445                 connection->state = SENT_DISCONNECT;
4446                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4447                 return true;
4448 
4449             default:
4450                 break;
4451         }
4452 
4453         // no further commands if connection is about to get shut down
4454         if (connection->state == SENT_DISCONNECT) continue;
4455 
4456         if (connection->authentication_flags & AUTH_FLAG_READ_RSSI){
4457             connectionClearAuthenticationFlags(connection, AUTH_FLAG_READ_RSSI);
4458             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4459             return true;
4460         }
4461 
4462 #ifdef ENABLE_CLASSIC
4463 
4464         if (connection->authentication_flags & AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT){
4465             connectionClearAuthenticationFlags(connection, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
4466             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4467             return true;
4468         }
4469 
4470         // Handling link key request requires remote supported features
4471         if (((connection->authentication_flags & AUTH_FLAG_HANDLE_LINK_KEY_REQUEST) != 0) && ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0)){
4472             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4473             connectionClearAuthenticationFlags(connection, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
4474 
4475             // lookup link key using cached key first
4476             bool have_link_key = connection->link_key_type != INVALID_LINK_KEY;
4477             if (!have_link_key && (hci_stack->link_key_db != NULL)){
4478                 have_link_key = hci_stack->link_key_db->get_link_key(connection->address, connection->link_key, &connection->link_key_type);
4479             }
4480 
4481             const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
4482             bool sc_enabled_remote = (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
4483             bool sc_downgrade = have_link_key && (gap_secure_connection_for_link_key_type(connection->link_key_type) == 1) && !sc_enabled_remote;
4484             if (sc_downgrade){
4485                 log_info("Link key based on SC, but remote does not support SC -> disconnect");
4486                 connection->state = SENT_DISCONNECT;
4487                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4488                 return true;
4489             }
4490 
4491             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(connection->link_key_type) >= connection->requested_security_level);
4492             if (have_link_key && security_level_sufficient){
4493                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &connection->link_key);
4494             } else {
4495                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4496             }
4497             return true;
4498         }
4499 
4500         if (connection->authentication_flags & AUTH_FLAG_DENY_PIN_CODE_REQUEST){
4501             log_info("denying to pin request");
4502             connectionClearAuthenticationFlags(connection, AUTH_FLAG_DENY_PIN_CODE_REQUEST);
4503             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4504             return true;
4505         }
4506 
4507         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY){
4508             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
4509             // set authentication requirements:
4510             // - MITM = ssp_authentication_requirement (USER) | requested_security_level (dynamic)
4511             // - BONDING MODE: dedicated if requested, bondable otherwise. Drop bondable if not set for remote
4512             uint8_t authreq = hci_stack->ssp_authentication_requirement & 1;
4513             if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4514                 authreq |= 1;
4515             }
4516             bool bonding = hci_stack->bondable;
4517             if (connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
4518                 // if we have received IO Cap Response, we're in responder role
4519                 bool remote_bonding = connection->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4520                 if (bonding && !remote_bonding){
4521                     log_info("Remote not bonding, dropping local flag");
4522                     bonding = false;
4523                 }
4524             }
4525             if (bonding){
4526                 if (connection->bonding_flags & BONDING_DEDICATED){
4527                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4528                 } else {
4529                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
4530                 }
4531             }
4532             uint8_t have_oob_data = 0;
4533 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4534             if (connection->classic_oob_c_192 != NULL){
4535                     have_oob_data |= 1;
4536             }
4537             if (connection->classic_oob_c_256 != NULL){
4538                 have_oob_data |= 2;
4539             }
4540 #endif
4541             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, have_oob_data, authreq);
4542             return true;
4543         }
4544 
4545         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY) {
4546             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
4547             hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4548             return true;
4549         }
4550 
4551 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4552         if (connection->authentication_flags & SEND_REMOTE_OOB_DATA_REPLY){
4553             connectionClearAuthenticationFlags(connection, SEND_REMOTE_OOB_DATA_REPLY);
4554             const uint8_t zero[16] = { 0 };
4555             const uint8_t * r_192 = zero;
4556             const uint8_t * c_192 = zero;
4557             const uint8_t * r_256 = zero;
4558             const uint8_t * c_256 = zero;
4559             // verify P-256 OOB
4560             if ((connection->classic_oob_c_256 != NULL) && ((hci_stack->local_supported_commands[1] & 0x08u) != 0)) {
4561                 c_256 = connection->classic_oob_c_256;
4562                 if (connection->classic_oob_r_256 != NULL) {
4563                     r_256 = connection->classic_oob_r_256;
4564                 }
4565             }
4566             // verify P-192 OOB
4567             if ((connection->classic_oob_c_192 != NULL)) {
4568                 c_192 = connection->classic_oob_c_192;
4569                 if (connection->classic_oob_r_192 != NULL) {
4570                     r_192 = connection->classic_oob_r_192;
4571                 }
4572             }
4573             // Reply
4574             if (c_256 != zero) {
4575                 hci_send_cmd(&hci_remote_oob_extended_data_request_reply, &connection->address, c_192, r_192, c_256, r_256);
4576             } else if (c_192 != zero){
4577                 hci_send_cmd(&hci_remote_oob_data_request_reply, &connection->address, c_192, r_192);
4578             } else {
4579                 hci_send_cmd(&hci_remote_oob_data_request_negative_reply, &connection->address);
4580             }
4581             return true;
4582         }
4583 #endif
4584 
4585         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_REPLY){
4586             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
4587             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4588             return true;
4589         }
4590 
4591         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_PASSKEY_REPLY){
4592             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
4593             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4594             return true;
4595         }
4596 
4597         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4598             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4599             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4600             return true;
4601         }
4602 
4603         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4604             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4605             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4606             return true;
4607         }
4608 
4609         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4610             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4611             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4612             return true;
4613         }
4614 
4615         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4616             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4617             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4618             connection->state = SENT_DISCONNECT;
4619             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4620             return true;
4621         }
4622 
4623         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
4624             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4625             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4626             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4627             return true;
4628         }
4629 
4630         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4631             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4632             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4633             return true;
4634         }
4635         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4636             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4637             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4638             return true;
4639         }
4640 #endif
4641 
4642         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4643             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4644 #ifdef ENABLE_CLASSIC
4645             hci_pairing_complete(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_SECURITY_REASONS);
4646 #endif
4647             if (connection->state != SENT_DISCONNECT){
4648                 connection->state = SENT_DISCONNECT;
4649                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4650                 return true;
4651             }
4652         }
4653 
4654 #ifdef ENABLE_CLASSIC
4655         uint16_t sniff_min_interval;
4656         switch (connection->sniff_min_interval){
4657             case 0:
4658                 break;
4659             case 0xffff:
4660                 connection->sniff_min_interval = 0;
4661                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4662                 return true;
4663             default:
4664                 sniff_min_interval = connection->sniff_min_interval;
4665                 connection->sniff_min_interval = 0;
4666                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4667                 return true;
4668         }
4669 
4670         if (connection->sniff_subrating_max_latency != 0xffff){
4671             uint16_t max_latency = connection->sniff_subrating_max_latency;
4672             connection->sniff_subrating_max_latency = 0;
4673             hci_send_cmd(&hci_sniff_subrating, connection->con_handle, max_latency, connection->sniff_subrating_min_remote_timeout, connection->sniff_subrating_min_local_timeout);
4674             return true;
4675         }
4676 
4677         if (connection->qos_service_type != HCI_SERVICE_TYPE_INVALID){
4678             uint8_t service_type = (uint8_t) connection->qos_service_type;
4679             connection->qos_service_type = HCI_SERVICE_TYPE_INVALID;
4680             hci_send_cmd(&hci_qos_setup, connection->con_handle, 0, service_type, connection->qos_token_rate, connection->qos_peak_bandwidth, connection->qos_latency, connection->qos_delay_variation);
4681             return true;
4682         }
4683 
4684         if (connection->request_role != HCI_ROLE_INVALID){
4685             hci_role_t role = connection->request_role;
4686             connection->request_role = HCI_ROLE_INVALID;
4687             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4688             return true;
4689         }
4690 #endif
4691 
4692 #ifdef ENABLE_BLE
4693         switch (connection->le_con_parameter_update_state){
4694             // response to L2CAP CON PARAMETER UPDATE REQUEST
4695             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4696                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4697                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4698                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4699                              0x0000, 0xffff);
4700                 return true;
4701             case CON_PARAMETER_UPDATE_REPLY:
4702                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4703                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4704                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4705                              0x0000, 0xffff);
4706                 return true;
4707             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4708                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4709                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4710                 return true;
4711             default:
4712                 break;
4713         }
4714         if (connection->le_phy_update_all_phys != 0xffu){
4715             uint8_t all_phys = connection->le_phy_update_all_phys;
4716             connection->le_phy_update_all_phys = 0xff;
4717             hci_send_cmd(&hci_le_set_phy, connection->con_handle, all_phys, connection->le_phy_update_tx_phys, connection->le_phy_update_rx_phys, connection->le_phy_update_phy_options);
4718             return true;
4719         }
4720 #endif
4721     }
4722     return false;
4723 }
4724 
4725 static void hci_run(void){
4726 
4727     bool done;
4728 
4729     // send continuation fragments first, as they block the prepared packet buffer
4730     done = hci_run_acl_fragments();
4731     if (done) return;
4732 
4733 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4734     // send host num completed packets next as they don't require num_cmd_packets > 0
4735     if (!hci_can_send_comand_packet_transport()) return;
4736     if (hci_stack->host_completed_packets){
4737         hci_host_num_completed_packets();
4738         return;
4739     }
4740 #endif
4741 
4742     if (!hci_can_send_command_packet_now()) return;
4743 
4744     // global/non-connection oriented commands
4745 
4746 
4747 #ifdef ENABLE_CLASSIC
4748     // general gap classic
4749     done = hci_run_general_gap_classic();
4750     if (done) return;
4751 #endif
4752 
4753 #ifdef ENABLE_BLE
4754     // general gap le
4755     done = hci_run_general_gap_le();
4756     if (done) return;
4757 #endif
4758 
4759     // send pending HCI commands
4760     done = hci_run_general_pending_commands();
4761     if (done) return;
4762 
4763     // stack state sub statemachines
4764     hci_connection_t * connection;
4765     switch (hci_stack->state){
4766         case HCI_STATE_INITIALIZING:
4767             hci_initializing_run();
4768             break;
4769 
4770         case HCI_STATE_HALTING:
4771 
4772             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4773             switch (hci_stack->substate){
4774                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4775                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
4776 
4777 #ifdef ENABLE_BLE
4778 #ifdef ENABLE_LE_CENTRAL
4779                     // free whitelist entries
4780                     {
4781                         btstack_linked_list_iterator_t lit;
4782                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4783                         while (btstack_linked_list_iterator_has_next(&lit)){
4784                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4785                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4786                             btstack_memory_whitelist_entry_free(entry);
4787                         }
4788                     }
4789 #endif
4790 #endif
4791                     // close all open connections
4792                     connection =  (hci_connection_t *) hci_stack->connections;
4793                     if (connection){
4794                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
4795                         if (!hci_can_send_command_packet_now()) return;
4796 
4797                         // check state
4798                         if (connection->state == SENT_DISCONNECT) return;
4799                         connection->state = SENT_DISCONNECT;
4800 
4801                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
4802 
4803                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
4804                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
4805 
4806                         // ... which would be ignored anyway as we shutdown (free) the connection now
4807                         hci_shutdown_connection(connection);
4808 
4809                         // finally, send the disconnect command
4810                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4811                         return;
4812                     }
4813 
4814                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
4815                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
4816                         log_info("HCI_STATE_HALTING: wait 50 ms");
4817                         hci_stack->substate = HCI_HALTING_W4_TIMER;
4818                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
4819                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
4820                         btstack_run_loop_add_timer(&hci_stack->timeout);
4821                         break;
4822                     }
4823 
4824                     /* fall through */
4825 
4826                 case HCI_HALTING_CLOSE:
4827                     log_info("HCI_STATE_HALTING, calling off");
4828 
4829                     // switch mode
4830                     hci_power_control_off();
4831 
4832                     log_info("HCI_STATE_HALTING, emitting state");
4833                     hci_emit_state();
4834                     log_info("HCI_STATE_HALTING, done");
4835                     break;
4836 
4837                 case HCI_HALTING_W4_TIMER:
4838                     // keep waiting
4839 
4840                     break;
4841                 default:
4842                     break;
4843             }
4844 
4845             break;
4846 
4847         case HCI_STATE_FALLING_ASLEEP:
4848             switch(hci_stack->substate) {
4849                 case HCI_FALLING_ASLEEP_DISCONNECT:
4850                     log_info("HCI_STATE_FALLING_ASLEEP");
4851                     // close all open connections
4852                     connection =  (hci_connection_t *) hci_stack->connections;
4853 
4854 #ifdef HAVE_PLATFORM_IPHONE_OS
4855                     // don't close connections, if H4 supports power management
4856                     if (btstack_control_iphone_power_management_enabled()){
4857                         connection = NULL;
4858                     }
4859 #endif
4860                     if (connection){
4861 
4862                         // send disconnect
4863                         if (!hci_can_send_command_packet_now()) return;
4864 
4865                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
4866                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4867 
4868                         // send disconnected event right away - causes higher layer connections to get closed, too.
4869                         hci_shutdown_connection(connection);
4870                         return;
4871                     }
4872 
4873                     if (hci_classic_supported()){
4874                         // disable page and inquiry scan
4875                         if (!hci_can_send_command_packet_now()) return;
4876 
4877                         log_info("HCI_STATE_HALTING, disabling inq scans");
4878                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
4879 
4880                         // continue in next sub state
4881                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
4882                         break;
4883                     }
4884 
4885                     /* fall through */
4886 
4887                 case HCI_FALLING_ASLEEP_COMPLETE:
4888                     log_info("HCI_STATE_HALTING, calling sleep");
4889 #ifdef HAVE_PLATFORM_IPHONE_OS
4890                     // don't actually go to sleep, if H4 supports power management
4891                     if (btstack_control_iphone_power_management_enabled()){
4892                         // SLEEP MODE reached
4893                         hci_stack->state = HCI_STATE_SLEEPING;
4894                         hci_emit_state();
4895                         break;
4896                     }
4897 #endif
4898                     // switch mode
4899                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
4900                     hci_emit_state();
4901                     break;
4902 
4903                 default:
4904                     break;
4905             }
4906             break;
4907 
4908         default:
4909             break;
4910     }
4911 }
4912 
4913 int hci_send_cmd_packet(uint8_t *packet, int size){
4914     // house-keeping
4915 
4916 #ifdef ENABLE_CLASSIC
4917     bd_addr_t addr;
4918     hci_connection_t * conn;
4919 #endif
4920 #ifdef ENABLE_LE_CENTRAL
4921     uint8_t initiator_filter_policy;
4922 #endif
4923 
4924     uint16_t opcode = little_endian_read_16(packet, 0);
4925     switch (opcode) {
4926         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
4927             hci_stack->loopback_mode = packet[3];
4928             break;
4929 
4930 #ifdef ENABLE_CLASSIC
4931         case HCI_OPCODE_HCI_CREATE_CONNECTION:
4932             reverse_bd_addr(&packet[3], addr);
4933             log_info("Create_connection to %s", bd_addr_to_str(addr));
4934 
4935             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4936             if (!conn) {
4937                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4938                 if (!conn) {
4939                     // notify client that alloc failed
4940                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4941                     return -1; // packet not sent to controller
4942                 }
4943                 conn->state = SEND_CREATE_CONNECTION;
4944                 conn->role  = HCI_ROLE_MASTER;
4945             }
4946             log_info("conn state %u", conn->state);
4947             switch (conn->state) {
4948                 // if connection active exists
4949                 case OPEN:
4950                     // and OPEN, emit connection complete command
4951                     hci_emit_connection_complete(addr, conn->con_handle, 0);
4952                     return -1; // packet not sent to controller
4953                 case RECEIVED_DISCONNECTION_COMPLETE:
4954                     // create connection triggered in disconnect complete event, let's do it now
4955                     break;
4956                 case SEND_CREATE_CONNECTION:
4957                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
4958                     break;
4959                 default:
4960                     // otherwise, just ignore as it is already in the open process
4961                     return -1; // packet not sent to controller
4962             }
4963             conn->state = SENT_CREATE_CONNECTION;
4964 
4965             // track outgoing connection
4966             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
4967             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
4968             break;
4969         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
4970             if (hci_stack->link_key_db) {
4971                 reverse_bd_addr(&packet[3], addr);
4972                 hci_stack->link_key_db->delete_link_key(addr);
4973             }
4974             break;
4975 
4976 #if defined (ENABLE_SCO_OVER_HCI) || defined (HAVE_SCO_TRANSPORT)
4977         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
4978             // setup_synchronous_connection? Voice setting at offset 22
4979             // TODO: compare to current setting if sco connection already active
4980             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
4981             break;
4982         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
4983             // accept_synchronus_connection? Voice setting at offset 18
4984             // TODO: compare to current setting if sco connection already active
4985             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
4986             break;
4987 #endif
4988 #endif
4989 
4990 #ifdef ENABLE_BLE
4991         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
4992             hci_stack->le_random_address_set = 1;
4993             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
4994             break;
4995 #ifdef ENABLE_LE_PERIPHERAL
4996         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
4997             hci_stack->le_advertisements_active = packet[3] != 0;
4998             break;
4999 #endif
5000 #ifdef ENABLE_LE_CENTRAL
5001         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
5002             // white list used?
5003             initiator_filter_policy = packet[7];
5004             switch (initiator_filter_policy) {
5005                 case 0:
5006                     // whitelist not used
5007                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
5008                     break;
5009                 case 1:
5010                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
5011                     break;
5012                 default:
5013                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
5014                     break;
5015             }
5016             // track outgoing connection
5017             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
5018             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
5019             break;
5020         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
5021             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
5022             break;
5023 #endif
5024 #endif
5025         default:
5026             break;
5027     }
5028 
5029     hci_stack->num_cmd_packets--;
5030 
5031     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
5032     return hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
5033 }
5034 
5035 // disconnect because of security block
5036 void hci_disconnect_security_block(hci_con_handle_t con_handle){
5037     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5038     if (!connection) return;
5039     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
5040 }
5041 
5042 
5043 // Configure Secure Simple Pairing
5044 
5045 #ifdef ENABLE_CLASSIC
5046 
5047 // enable will enable SSP during init
5048 void gap_ssp_set_enable(int enable){
5049     hci_stack->ssp_enable = enable;
5050 }
5051 
5052 static int hci_local_ssp_activated(void){
5053     return gap_ssp_supported() && hci_stack->ssp_enable;
5054 }
5055 
5056 // if set, BTstack will respond to io capability request using authentication requirement
5057 void gap_ssp_set_io_capability(int io_capability){
5058     hci_stack->ssp_io_capability = io_capability;
5059 }
5060 void gap_ssp_set_authentication_requirement(int authentication_requirement){
5061     hci_stack->ssp_authentication_requirement = authentication_requirement;
5062 }
5063 
5064 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
5065 void gap_ssp_set_auto_accept(int auto_accept){
5066     hci_stack->ssp_auto_accept = auto_accept;
5067 }
5068 
5069 void gap_secure_connections_enable(bool enable){
5070     hci_stack->secure_connections_enable = enable;
5071 }
5072 
5073 #endif
5074 
5075 // va_list part of hci_send_cmd
5076 int hci_send_cmd_va_arg(const hci_cmd_t * cmd, va_list argptr){
5077     if (!hci_can_send_command_packet_now()){
5078         log_error("hci_send_cmd called but cannot send packet now");
5079         return 0;
5080     }
5081 
5082     // for HCI INITIALIZATION
5083     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
5084     hci_stack->last_cmd_opcode = cmd->opcode;
5085 
5086     hci_reserve_packet_buffer();
5087     uint8_t * packet = hci_stack->hci_packet_buffer;
5088     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
5089     int err = hci_send_cmd_packet(packet, size);
5090 
5091     // release packet buffer on error or for synchronous transport implementations
5092     if ((err < 0) || hci_transport_synchronous()){
5093         hci_release_packet_buffer();
5094         hci_emit_transport_packet_sent();
5095     }
5096 
5097     return err;
5098 }
5099 
5100 /**
5101  * pre: numcmds >= 0 - it's allowed to send a command to the controller
5102  */
5103 int hci_send_cmd(const hci_cmd_t * cmd, ...){
5104     va_list argptr;
5105     va_start(argptr, cmd);
5106     int res = hci_send_cmd_va_arg(cmd, argptr);
5107     va_end(argptr);
5108     return res;
5109 }
5110 
5111 // Create various non-HCI events.
5112 // TODO: generalize, use table similar to hci_create_command
5113 
5114 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
5115     // dump packet
5116     if (dump) {
5117         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
5118     }
5119 
5120     // dispatch to all event handlers
5121     btstack_linked_list_iterator_t it;
5122     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
5123     while (btstack_linked_list_iterator_has_next(&it)){
5124         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
5125         entry->callback(HCI_EVENT_PACKET, 0, event, size);
5126     }
5127 }
5128 
5129 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
5130     if (!hci_stack->acl_packet_handler) return;
5131     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
5132 }
5133 
5134 #ifdef ENABLE_CLASSIC
5135 static void hci_notify_if_sco_can_send_now(void){
5136     // notify SCO sender if waiting
5137     if (!hci_stack->sco_waiting_for_can_send_now) return;
5138     if (hci_can_send_sco_packet_now()){
5139         hci_stack->sco_waiting_for_can_send_now = 0;
5140         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
5141         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
5142         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
5143     }
5144 }
5145 
5146 // parsing end emitting has been merged to reduce code size
5147 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
5148     uint8_t event[28+GAP_INQUIRY_MAX_NAME_LEN];
5149 
5150     uint8_t * eir_data;
5151     ad_context_t context;
5152     const uint8_t * name;
5153     uint8_t         name_len;
5154 
5155     if (size < 3) return;
5156 
5157     int event_type = hci_event_packet_get_type(packet);
5158     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
5159     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
5160 
5161     switch (event_type){
5162         case HCI_EVENT_INQUIRY_RESULT:
5163         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5164             if (size != (3 + (num_responses * 14))) return;
5165             break;
5166         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5167             if (size != 257) return;
5168             if (num_responses != 1) return;
5169             break;
5170         default:
5171             return;
5172     }
5173 
5174     // event[1] is set at the end
5175     int i;
5176     for (i=0; i<num_responses;i++){
5177         memset(event, 0, sizeof(event));
5178         event[0] = GAP_EVENT_INQUIRY_RESULT;
5179         uint8_t event_size = 18;    // if name is not set by EIR
5180 
5181         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
5182         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
5183         (void)memcpy(&event[9],
5184                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
5185                      3); // class of device
5186         (void)memcpy(&event[12],
5187                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
5188                      2); // clock offset
5189 
5190         switch (event_type){
5191             case HCI_EVENT_INQUIRY_RESULT:
5192                 // 14,15,16,17 = 0, size 18
5193                 break;
5194             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5195                 event[14] = 1;
5196                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5197                 // 16,17 = 0, size 18
5198                 break;
5199             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5200                 event[14] = 1;
5201                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5202                 // EIR packets only contain a single inquiry response
5203                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
5204                 name = NULL;
5205                 // Iterate over EIR data
5206                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
5207                     uint8_t data_type    = ad_iterator_get_data_type(&context);
5208                     uint8_t data_size    = ad_iterator_get_data_len(&context);
5209                     const uint8_t * data = ad_iterator_get_data(&context);
5210                     // Prefer Complete Local Name over Shortened Local Name
5211                     switch (data_type){
5212                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
5213                             if (name) continue;
5214                             /* fall through */
5215                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
5216                             name = data;
5217                             name_len = data_size;
5218                             break;
5219                         case BLUETOOTH_DATA_TYPE_DEVICE_ID:
5220                             if (data_size != 8) break;
5221                             event[16] = 1;
5222                             memcpy(&event[17], data, 8);
5223                             break;
5224                         default:
5225                             break;
5226                     }
5227                 }
5228                 if (name){
5229                     event[25] = 1;
5230                     // truncate name if needed
5231                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
5232                     event[26] = len;
5233                     (void)memcpy(&event[27], name, len);
5234                     event_size += len;
5235                 }
5236                 break;
5237             default:
5238                 return;
5239         }
5240         event[1] = event_size - 2;
5241         hci_emit_event(event, event_size, 1);
5242     }
5243 }
5244 #endif
5245 
5246 void hci_emit_state(void){
5247     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
5248     uint8_t event[3];
5249     event[0] = BTSTACK_EVENT_STATE;
5250     event[1] = sizeof(event) - 2u;
5251     event[2] = hci_stack->state;
5252     hci_emit_event(event, sizeof(event), 1);
5253 }
5254 
5255 #ifdef ENABLE_CLASSIC
5256 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5257     uint8_t event[13];
5258     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
5259     event[1] = sizeof(event) - 2;
5260     event[2] = status;
5261     little_endian_store_16(event, 3, con_handle);
5262     reverse_bd_addr(address, &event[5]);
5263     event[11] = 1; // ACL connection
5264     event[12] = 0; // encryption disabled
5265     hci_emit_event(event, sizeof(event), 1);
5266 }
5267 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
5268     if (disable_l2cap_timeouts) return;
5269     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
5270     uint8_t event[4];
5271     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
5272     event[1] = sizeof(event) - 2;
5273     little_endian_store_16(event, 2, conn->con_handle);
5274     hci_emit_event(event, sizeof(event), 1);
5275 }
5276 #endif
5277 
5278 #ifdef ENABLE_BLE
5279 #ifdef ENABLE_LE_CENTRAL
5280 static void hci_emit_le_connection_complete(uint8_t address_type, const bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5281     uint8_t event[21];
5282     event[0] = HCI_EVENT_LE_META;
5283     event[1] = sizeof(event) - 2u;
5284     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
5285     event[3] = status;
5286     little_endian_store_16(event, 4, con_handle);
5287     event[6] = 0; // TODO: role
5288     event[7] = address_type;
5289     reverse_bd_addr(address, &event[8]);
5290     little_endian_store_16(event, 14, 0); // interval
5291     little_endian_store_16(event, 16, 0); // latency
5292     little_endian_store_16(event, 18, 0); // supervision timeout
5293     event[20] = 0; // master clock accuracy
5294     hci_emit_event(event, sizeof(event), 1);
5295 }
5296 #endif
5297 #endif
5298 
5299 static void hci_emit_transport_packet_sent(void){
5300     // notify upper stack that it might be possible to send again
5301     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
5302     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
5303 }
5304 
5305 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
5306     uint8_t event[6];
5307     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
5308     event[1] = sizeof(event) - 2u;
5309     event[2] = 0; // status = OK
5310     little_endian_store_16(event, 3, con_handle);
5311     event[5] = reason;
5312     hci_emit_event(event, sizeof(event), 1);
5313 }
5314 
5315 static void hci_emit_nr_connections_changed(void){
5316     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
5317     uint8_t event[3];
5318     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
5319     event[1] = sizeof(event) - 2u;
5320     event[2] = nr_hci_connections();
5321     hci_emit_event(event, sizeof(event), 1);
5322 }
5323 
5324 static void hci_emit_hci_open_failed(void){
5325     log_info("BTSTACK_EVENT_POWERON_FAILED");
5326     uint8_t event[2];
5327     event[0] = BTSTACK_EVENT_POWERON_FAILED;
5328     event[1] = sizeof(event) - 2u;
5329     hci_emit_event(event, sizeof(event), 1);
5330 }
5331 
5332 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
5333     log_info("hci_emit_dedicated_bonding_result %u ", status);
5334     uint8_t event[9];
5335     int pos = 0;
5336     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
5337     event[pos++] = sizeof(event) - 2u;
5338     event[pos++] = status;
5339     reverse_bd_addr(address, &event[pos]);
5340     hci_emit_event(event, sizeof(event), 1);
5341 }
5342 
5343 
5344 #ifdef ENABLE_CLASSIC
5345 
5346 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
5347     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
5348     uint8_t event[5];
5349     int pos = 0;
5350     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
5351     event[pos++] = sizeof(event) - 2;
5352     little_endian_store_16(event, 2, con_handle);
5353     pos += 2;
5354     event[pos++] = level;
5355     hci_emit_event(event, sizeof(event), 1);
5356 }
5357 
5358 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
5359     if (!connection) return LEVEL_0;
5360     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
5361     // BIAS: we only consider Authenticated if the connection is already encrypted, which requires that both sides have link key
5362     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
5363     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
5364     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
5365     // LEVEL 4 always requires 128 bit encrytion key size
5366     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
5367         security_level = LEVEL_3;
5368     }
5369     return security_level;
5370 }
5371 
5372 static void hci_emit_discoverable_enabled(uint8_t enabled){
5373     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
5374     uint8_t event[3];
5375     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
5376     event[1] = sizeof(event) - 2;
5377     event[2] = enabled;
5378     hci_emit_event(event, sizeof(event), 1);
5379 }
5380 
5381 // query if remote side supports eSCO
5382 int hci_remote_esco_supported(hci_con_handle_t con_handle){
5383     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5384     if (!connection) return 0;
5385     return (connection->remote_supported_features[0] & 1) != 0;
5386 }
5387 
5388 static bool hci_ssp_supported(hci_connection_t * connection){
5389     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
5390     return (connection->bonding_flags & mask) == mask;
5391 }
5392 
5393 // query if remote side supports SSP
5394 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
5395     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5396     if (!connection) return 0;
5397     return hci_ssp_supported(connection) ? 1 : 0;
5398 }
5399 
5400 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
5401     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
5402 }
5403 
5404 // GAP API
5405 /**
5406  * @bbrief enable/disable bonding. default is enabled
5407  * @praram enabled
5408  */
5409 void gap_set_bondable_mode(int enable){
5410     hci_stack->bondable = enable ? 1 : 0;
5411 }
5412 /**
5413  * @brief Get bondable mode.
5414  * @return 1 if bondable
5415  */
5416 int gap_get_bondable_mode(void){
5417     return hci_stack->bondable;
5418 }
5419 
5420 /**
5421  * @brief map link keys to security levels
5422  */
5423 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
5424     switch (link_key_type){
5425         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5426             return LEVEL_4;
5427         case COMBINATION_KEY:
5428         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5429             return LEVEL_3;
5430         default:
5431             return LEVEL_2;
5432     }
5433 }
5434 
5435 /**
5436  * @brief map link keys to secure connection yes/no
5437  */
5438 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5439     switch (link_key_type){
5440         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5441         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5442             return 1;
5443         default:
5444             return 0;
5445     }
5446 }
5447 
5448 /**
5449  * @brief map link keys to authenticated
5450  */
5451 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5452     switch (link_key_type){
5453         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5454         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5455             return 1;
5456         default:
5457             return 0;
5458     }
5459 }
5460 
5461 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5462     log_info("gap_mitm_protection_required_for_security_level %u", level);
5463     return level > LEVEL_2;
5464 }
5465 
5466 /**
5467  * @brief get current security level
5468  */
5469 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5470     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5471     if (!connection) return LEVEL_0;
5472     return gap_security_level_for_connection(connection);
5473 }
5474 
5475 /**
5476  * @brief request connection to device to
5477  * @result GAP_AUTHENTICATION_RESULT
5478  */
5479 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5480     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5481     if (!connection){
5482         hci_emit_security_level(con_handle, LEVEL_0);
5483         return;
5484     }
5485 
5486     btstack_assert(hci_is_le_connection(connection) == false);
5487 
5488     gap_security_level_t current_level = gap_security_level(con_handle);
5489     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5490         requested_level, connection->requested_security_level, current_level);
5491 
5492     // authentication active if authentication request was sent or planned level > 0
5493     bool authentication_active = ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) || (connection->requested_security_level > LEVEL_0);
5494     if (authentication_active){
5495         // authentication already active
5496         if (connection->requested_security_level < requested_level){
5497             // increase requested level as new level is higher
5498             // TODO: handle re-authentication when done
5499             connection->requested_security_level = requested_level;
5500         }
5501     } else {
5502         // no request active, notify if security sufficient
5503         if (requested_level <= current_level){
5504             hci_emit_security_level(con_handle, current_level);
5505             return;
5506         }
5507 
5508         // store request
5509         connection->requested_security_level = requested_level;
5510 
5511         // start to authenticate connection
5512         connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5513         hci_run();
5514     }
5515 }
5516 
5517 /**
5518  * @brief start dedicated bonding with device. disconnect after bonding
5519  * @param device
5520  * @param request MITM protection
5521  * @result GAP_DEDICATED_BONDING_COMPLETE
5522  */
5523 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5524 
5525     // create connection state machine
5526     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5527 
5528     if (!connection){
5529         return BTSTACK_MEMORY_ALLOC_FAILED;
5530     }
5531 
5532     // delete linkn key
5533     gap_drop_link_key_for_bd_addr(device);
5534 
5535     // configure LEVEL_2/3, dedicated bonding
5536     connection->state = SEND_CREATE_CONNECTION;
5537     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5538     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5539     connection->bonding_flags = BONDING_DEDICATED;
5540 
5541     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5542 
5543     // handle: connnection failure (connection complete != ok)
5544     // handle: authentication failure
5545     // handle: disconnect on done
5546 
5547     hci_run();
5548 
5549     return 0;
5550 }
5551 #endif
5552 
5553 void gap_set_local_name(const char * local_name){
5554     hci_stack->local_name = local_name;
5555 }
5556 
5557 
5558 #ifdef ENABLE_BLE
5559 
5560 #ifdef ENABLE_LE_CENTRAL
5561 void gap_start_scan(void){
5562     hci_stack->le_scanning_enabled = true;
5563     hci_run();
5564 }
5565 
5566 void gap_stop_scan(void){
5567     hci_stack->le_scanning_enabled = false;
5568     hci_run();
5569 }
5570 
5571 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5572     hci_stack->le_scan_type          = scan_type;
5573     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5574     hci_stack->le_scan_interval      = scan_interval;
5575     hci_stack->le_scan_window        = scan_window;
5576     hci_stack->le_scanning_param_update = true;
5577     hci_run();
5578 }
5579 
5580 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5581     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5582 }
5583 
5584 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5585     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5586     if (!conn){
5587         // disallow if le connection is already outgoing
5588         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5589             log_error("le connection already active");
5590             return ERROR_CODE_COMMAND_DISALLOWED;
5591         }
5592 
5593         log_info("gap_connect: no connection exists yet, creating context");
5594         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5595         if (!conn){
5596             // notify client that alloc failed
5597             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5598             log_info("gap_connect: failed to alloc hci_connection_t");
5599             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5600         }
5601 
5602         // set le connecting state
5603         if (hci_is_le_connection_type(addr_type)){
5604             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5605         }
5606 
5607         conn->state = SEND_CREATE_CONNECTION;
5608         log_info("gap_connect: send create connection next");
5609         hci_run();
5610         return ERROR_CODE_SUCCESS;
5611     }
5612 
5613     if (!hci_is_le_connection(conn) ||
5614         (conn->state == SEND_CREATE_CONNECTION) ||
5615         (conn->state == SENT_CREATE_CONNECTION)) {
5616         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5617         log_error("gap_connect: classic connection or connect is already being created");
5618         return GATT_CLIENT_IN_WRONG_STATE;
5619     }
5620 
5621     // check if connection was just disconnected
5622     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5623         log_info("gap_connect: send create connection (again)");
5624         conn->state = SEND_CREATE_CONNECTION;
5625         hci_run();
5626         return ERROR_CODE_SUCCESS;
5627     }
5628 
5629     log_info("gap_connect: context exists with state %u", conn->state);
5630     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5631     hci_run();
5632     return ERROR_CODE_SUCCESS;
5633 }
5634 
5635 // @assumption: only a single outgoing LE Connection exists
5636 static hci_connection_t * gap_get_outgoing_connection(void){
5637     btstack_linked_item_t *it;
5638     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5639         hci_connection_t * conn = (hci_connection_t *) it;
5640         if (!hci_is_le_connection(conn)) continue;
5641         switch (conn->state){
5642             case SEND_CREATE_CONNECTION:
5643             case SENT_CREATE_CONNECTION:
5644             case SENT_CANCEL_CONNECTION:
5645                 return conn;
5646             default:
5647                 break;
5648         };
5649     }
5650     return NULL;
5651 }
5652 
5653 uint8_t gap_connect_cancel(void){
5654     hci_connection_t * conn = gap_get_outgoing_connection();
5655     if (!conn) return 0;
5656     switch (conn->state){
5657         case SEND_CREATE_CONNECTION:
5658             // skip sending create connection and emit event instead
5659             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5660             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5661             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5662             btstack_memory_hci_connection_free( conn );
5663             break;
5664         case SENT_CREATE_CONNECTION:
5665             // request to send cancel connection
5666             conn->state = SEND_CANCEL_CONNECTION;
5667             hci_run();
5668             break;
5669         default:
5670             break;
5671     }
5672     return 0;
5673 }
5674 #endif
5675 
5676 #ifdef ENABLE_LE_CENTRAL
5677 /**
5678  * @brief Set connection parameters for outgoing connections
5679  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5680  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5681  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5682  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5683  * @param conn_latency, default: 4
5684  * @param supervision_timeout (unit: 10ms), default: 720 ms
5685  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5686  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5687  */
5688 
5689 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5690     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5691     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5692     hci_stack->le_connection_scan_interval = conn_scan_interval;
5693     hci_stack->le_connection_scan_window = conn_scan_window;
5694     hci_stack->le_connection_interval_min = conn_interval_min;
5695     hci_stack->le_connection_interval_max = conn_interval_max;
5696     hci_stack->le_connection_latency = conn_latency;
5697     hci_stack->le_supervision_timeout = supervision_timeout;
5698     hci_stack->le_minimum_ce_length = min_ce_length;
5699     hci_stack->le_maximum_ce_length = max_ce_length;
5700 }
5701 #endif
5702 
5703 /**
5704  * @brief Updates the connection parameters for a given LE connection
5705  * @param handle
5706  * @param conn_interval_min (unit: 1.25ms)
5707  * @param conn_interval_max (unit: 1.25ms)
5708  * @param conn_latency
5709  * @param supervision_timeout (unit: 10ms)
5710  * @returns 0 if ok
5711  */
5712 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5713     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5714     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5715     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5716     connection->le_conn_interval_min = conn_interval_min;
5717     connection->le_conn_interval_max = conn_interval_max;
5718     connection->le_conn_latency = conn_latency;
5719     connection->le_supervision_timeout = supervision_timeout;
5720     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5721     hci_run();
5722     return 0;
5723 }
5724 
5725 /**
5726  * @brief Request an update of the connection parameter for a given LE connection
5727  * @param handle
5728  * @param conn_interval_min (unit: 1.25ms)
5729  * @param conn_interval_max (unit: 1.25ms)
5730  * @param conn_latency
5731  * @param supervision_timeout (unit: 10ms)
5732  * @returns 0 if ok
5733  */
5734 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5735     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5736     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5737     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5738     connection->le_conn_interval_min = conn_interval_min;
5739     connection->le_conn_interval_max = conn_interval_max;
5740     connection->le_conn_latency = conn_latency;
5741     connection->le_supervision_timeout = supervision_timeout;
5742     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5743     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5744     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5745     return 0;
5746 }
5747 
5748 #ifdef ENABLE_LE_PERIPHERAL
5749 
5750 /**
5751  * @brief Set Advertisement Data
5752  * @param advertising_data_length
5753  * @param advertising_data (max 31 octets)
5754  * @note data is not copied, pointer has to stay valid
5755  */
5756 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
5757     hci_stack->le_advertisements_data_len = advertising_data_length;
5758     hci_stack->le_advertisements_data = advertising_data;
5759     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
5760     hci_run();
5761 }
5762 
5763 /**
5764  * @brief Set Scan Response Data
5765  * @param advertising_data_length
5766  * @param advertising_data (max 31 octets)
5767  * @note data is not copied, pointer has to stay valid
5768  */
5769 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
5770     hci_stack->le_scan_response_data_len = scan_response_data_length;
5771     hci_stack->le_scan_response_data = scan_response_data;
5772     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
5773     hci_run();
5774 }
5775 
5776 /**
5777  * @brief Set Advertisement Parameters
5778  * @param adv_int_min
5779  * @param adv_int_max
5780  * @param adv_type
5781  * @param direct_address_type
5782  * @param direct_address
5783  * @param channel_map
5784  * @param filter_policy
5785  *
5786  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
5787  */
5788  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
5789     uint8_t direct_address_typ, bd_addr_t direct_address,
5790     uint8_t channel_map, uint8_t filter_policy) {
5791 
5792     hci_stack->le_advertisements_interval_min = adv_int_min;
5793     hci_stack->le_advertisements_interval_max = adv_int_max;
5794     hci_stack->le_advertisements_type = adv_type;
5795     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
5796     hci_stack->le_advertisements_channel_map = channel_map;
5797     hci_stack->le_advertisements_filter_policy = filter_policy;
5798     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
5799                  6);
5800 
5801     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS | LE_ADVERTISEMENT_TASKS_PARAMS_SET;
5802     hci_run();
5803  }
5804 
5805 /**
5806  * @brief Enable/Disable Advertisements
5807  * @param enabled
5808  */
5809 void gap_advertisements_enable(int enabled){
5810     hci_stack->le_advertisements_enabled = enabled != 0;
5811     hci_update_advertisements_enabled_for_current_roles();
5812     hci_run();
5813 }
5814 
5815 #endif
5816 
5817 void hci_le_set_own_address_type(uint8_t own_address_type){
5818     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
5819     if (own_address_type == hci_stack->le_own_addr_type) return;
5820     hci_stack->le_own_addr_type = own_address_type;
5821 
5822 #ifdef ENABLE_LE_PERIPHERAL
5823     // update advertisement parameters, too
5824     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5825     hci_run();
5826 #endif
5827 #ifdef ENABLE_LE_CENTRAL
5828     // note: we don't update scan parameters or modify ongoing connection attempts
5829 #endif
5830 }
5831 
5832 #endif
5833 
5834 uint8_t gap_disconnect(hci_con_handle_t handle){
5835     hci_connection_t * conn = hci_connection_for_handle(handle);
5836     if (!conn){
5837         hci_emit_disconnection_complete(handle, 0);
5838         return 0;
5839     }
5840     // ignore if already disconnected
5841     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5842         return 0;
5843     }
5844     conn->state = SEND_DISCONNECT;
5845     hci_run();
5846     return 0;
5847 }
5848 
5849 int gap_read_rssi(hci_con_handle_t con_handle){
5850     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5851     if (hci_connection == NULL) return 0;
5852     connectionSetAuthenticationFlags(hci_connection, AUTH_FLAG_READ_RSSI);
5853     hci_run();
5854     return 1;
5855 }
5856 
5857 /**
5858  * @brief Get connection type
5859  * @param con_handle
5860  * @result connection_type
5861  */
5862 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
5863     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5864     if (!conn) return GAP_CONNECTION_INVALID;
5865     switch (conn->address_type){
5866         case BD_ADDR_TYPE_LE_PUBLIC:
5867         case BD_ADDR_TYPE_LE_RANDOM:
5868             return GAP_CONNECTION_LE;
5869         case BD_ADDR_TYPE_SCO:
5870             return GAP_CONNECTION_SCO;
5871         case BD_ADDR_TYPE_ACL:
5872             return GAP_CONNECTION_ACL;
5873         default:
5874             return GAP_CONNECTION_INVALID;
5875     }
5876 }
5877 
5878 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
5879     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5880     if (!conn) return HCI_ROLE_INVALID;
5881     return (hci_role_t) conn->role;
5882 }
5883 
5884 
5885 #ifdef ENABLE_CLASSIC
5886 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
5887     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5888     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5889     conn->request_role = role;
5890     hci_run();
5891     return ERROR_CODE_SUCCESS;
5892 }
5893 #endif
5894 
5895 #ifdef ENABLE_BLE
5896 
5897 uint8_t gap_le_set_phy(hci_con_handle_t con_handle, uint8_t all_phys, uint8_t tx_phys, uint8_t rx_phys, uint8_t phy_options){
5898     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5899     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5900 
5901     conn->le_phy_update_all_phys    = all_phys;
5902     conn->le_phy_update_tx_phys     = tx_phys;
5903     conn->le_phy_update_rx_phys     = rx_phys;
5904     conn->le_phy_update_phy_options = phy_options;
5905 
5906     hci_run();
5907 
5908     return 0;
5909 }
5910 
5911 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
5912     // check if already in list
5913     btstack_linked_list_iterator_t it;
5914     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5915     while (btstack_linked_list_iterator_has_next(&it)) {
5916         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
5917         if (entry->address_type != address_type) {
5918             continue;
5919         }
5920         if (memcmp(entry->address, address, 6) != 0) {
5921             continue;
5922         }
5923 		// disallow if already scheduled to add
5924 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
5925 			return ERROR_CODE_COMMAND_DISALLOWED;
5926 		}
5927 		// still on controller, but scheduled to remove -> re-add
5928 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
5929 		return ERROR_CODE_SUCCESS;
5930     }
5931     // alloc and add to list
5932     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
5933     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
5934     entry->address_type = address_type;
5935     (void)memcpy(entry->address, address, 6);
5936     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
5937     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
5938     return ERROR_CODE_SUCCESS;
5939 }
5940 
5941 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
5942     btstack_linked_list_iterator_t it;
5943     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5944     while (btstack_linked_list_iterator_has_next(&it)){
5945         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5946         if (entry->address_type != address_type) {
5947             continue;
5948         }
5949         if (memcmp(entry->address, address, 6) != 0) {
5950             continue;
5951         }
5952         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5953             // remove from controller if already present
5954             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5955         }  else {
5956             // directly remove entry from whitelist
5957             btstack_linked_list_iterator_remove(&it);
5958             btstack_memory_whitelist_entry_free(entry);
5959         }
5960         return ERROR_CODE_SUCCESS;
5961     }
5962     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5963 }
5964 
5965 static void hci_whitelist_clear(void){
5966     btstack_linked_list_iterator_t it;
5967     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5968     while (btstack_linked_list_iterator_has_next(&it)){
5969         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5970         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5971             // remove from controller if already present
5972             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5973             continue;
5974         }
5975         // directly remove entry from whitelist
5976         btstack_linked_list_iterator_remove(&it);
5977         btstack_memory_whitelist_entry_free(entry);
5978     }
5979 }
5980 
5981 /**
5982  * @brief Clear Whitelist
5983  * @returns 0 if ok
5984  */
5985 uint8_t gap_whitelist_clear(void){
5986     hci_whitelist_clear();
5987     hci_run();
5988     return ERROR_CODE_SUCCESS;
5989 }
5990 
5991 /**
5992  * @brief Add Device to Whitelist
5993  * @param address_typ
5994  * @param address
5995  * @returns 0 if ok
5996  */
5997 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
5998     uint8_t status = hci_whitelist_add(address_type, address);
5999     if (status){
6000         return status;
6001     }
6002     hci_run();
6003     return ERROR_CODE_SUCCESS;
6004 }
6005 
6006 /**
6007  * @brief Remove Device from Whitelist
6008  * @param address_typ
6009  * @param address
6010  * @returns 0 if ok
6011  */
6012 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6013     uint8_t status = hci_whitelist_remove(address_type, address);
6014     if (status){
6015         return status;
6016     }
6017     hci_run();
6018     return ERROR_CODE_SUCCESS;
6019 }
6020 
6021 #ifdef ENABLE_LE_CENTRAL
6022 /**
6023  *  @brief Connect with Whitelist
6024  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
6025  *  @returns - if ok
6026  */
6027 uint8_t gap_connect_with_whitelist(void){
6028     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
6029         return ERROR_CODE_COMMAND_DISALLOWED;
6030     }
6031     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6032     hci_run();
6033     return ERROR_CODE_SUCCESS;
6034 }
6035 
6036 /**
6037  * @brief Auto Connection Establishment - Start Connecting to device
6038  * @param address_typ
6039  * @param address
6040  * @returns 0 if ok
6041  */
6042 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
6043     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6044         return ERROR_CODE_COMMAND_DISALLOWED;
6045     }
6046 
6047     uint8_t status = hci_whitelist_add(address_type, address);
6048     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
6049         return status;
6050     }
6051 
6052     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6053 
6054     hci_run();
6055     return ERROR_CODE_SUCCESS;
6056 }
6057 
6058 /**
6059  * @brief Auto Connection Establishment - Stop Connecting to device
6060  * @param address_typ
6061  * @param address
6062  * @returns 0 if ok
6063  */
6064 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
6065     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6066         return ERROR_CODE_COMMAND_DISALLOWED;
6067     }
6068 
6069     hci_whitelist_remove(address_type, address);
6070     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
6071         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6072     }
6073     hci_run();
6074     return 0;
6075 }
6076 
6077 /**
6078  * @brief Auto Connection Establishment - Stop everything
6079  * @note  Convenience function to stop all active auto connection attempts
6080  */
6081 uint8_t gap_auto_connection_stop_all(void){
6082     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
6083         return ERROR_CODE_COMMAND_DISALLOWED;
6084     }
6085     hci_whitelist_clear();
6086     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6087     hci_run();
6088     return ERROR_CODE_SUCCESS;
6089 }
6090 
6091 uint16_t gap_le_connection_interval(hci_con_handle_t con_handle){
6092     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6093     if (!conn) return 0;
6094     return conn->le_connection_interval;
6095 }
6096 #endif
6097 #endif
6098 
6099 #ifdef ENABLE_CLASSIC
6100 /**
6101  * @brief Set Extended Inquiry Response data
6102  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
6103  * @note has to be done before stack starts up
6104  */
6105 void gap_set_extended_inquiry_response(const uint8_t * data){
6106     hci_stack->eir_data = data;
6107 }
6108 
6109 /**
6110  * @brief Start GAP Classic Inquiry
6111  * @param duration in 1.28s units
6112  * @return 0 if ok
6113  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
6114  */
6115 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
6116     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
6117     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6118     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
6119         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
6120     }
6121     hci_stack->inquiry_state = duration_in_1280ms_units;
6122     hci_run();
6123     return 0;
6124 }
6125 
6126 /**
6127  * @brief Stop GAP Classic Inquiry
6128  * @returns 0 if ok
6129  */
6130 int gap_inquiry_stop(void){
6131     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
6132         // emit inquiry complete event, before it even started
6133         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
6134         hci_emit_event(event, sizeof(event), 1);
6135         return 0;
6136     }
6137     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
6138     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
6139     hci_run();
6140     return 0;
6141 }
6142 
6143 void gap_inquiry_set_lap(uint32_t lap){
6144     hci_stack->inquiry_lap = lap;
6145 }
6146 
6147 
6148 /**
6149  * @brief Remote Name Request
6150  * @param addr
6151  * @param page_scan_repetition_mode
6152  * @param clock_offset only used when bit 15 is set
6153  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
6154  */
6155 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
6156     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6157     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
6158     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
6159     hci_stack->remote_name_clock_offset = clock_offset;
6160     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
6161     hci_run();
6162     return 0;
6163 }
6164 
6165 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
6166     hci_stack->gap_pairing_state = state;
6167     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
6168     hci_run();
6169     return 0;
6170 }
6171 
6172 /**
6173  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
6174  * @param addr
6175  * @param pin_data
6176  * @param pin_len
6177  * @return 0 if ok
6178  */
6179 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
6180     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6181     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
6182     hci_stack->gap_pairing_pin_len = pin_len;
6183     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
6184 }
6185 
6186 /**
6187  * @brief Legacy Pairing Pin Code Response
6188  * @param addr
6189  * @param pin
6190  * @return 0 if ok
6191  */
6192 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
6193     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
6194 }
6195 
6196 /**
6197  * @brief Abort Legacy Pairing
6198  * @param addr
6199  * @param pin
6200  * @return 0 if ok
6201  */
6202 int gap_pin_code_negative(bd_addr_t addr){
6203     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6204     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
6205 }
6206 
6207 /**
6208  * @brief SSP Passkey Response
6209  * @param addr
6210  * @param passkey
6211  * @return 0 if ok
6212  */
6213 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
6214     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6215     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
6216     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
6217 }
6218 
6219 /**
6220  * @brief Abort SSP Passkey Entry/Pairing
6221  * @param addr
6222  * @param pin
6223  * @return 0 if ok
6224  */
6225 int gap_ssp_passkey_negative(const bd_addr_t addr){
6226     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6227     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
6228 }
6229 
6230 /**
6231  * @brief Accept SSP Numeric Comparison
6232  * @param addr
6233  * @param passkey
6234  * @return 0 if ok
6235  */
6236 int gap_ssp_confirmation_response(const bd_addr_t addr){
6237     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6238     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
6239 }
6240 
6241 /**
6242  * @brief Abort SSP Numeric Comparison/Pairing
6243  * @param addr
6244  * @param pin
6245  * @return 0 if ok
6246  */
6247 int gap_ssp_confirmation_negative(const bd_addr_t addr){
6248     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6249     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
6250 }
6251 
6252 #ifdef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
6253 
6254 static uint8_t gap_set_auth_flag_and_run(const bd_addr_t addr, hci_authentication_flags_t flag){
6255     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6256     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6257     connectionSetAuthenticationFlags(conn, flag);
6258     hci_run();
6259     return ERROR_CODE_SUCCESS;
6260 }
6261 
6262 uint8_t gap_ssp_io_capabilities_response(const bd_addr_t addr){
6263     return gap_set_auth_flag_and_run(addr, SEND_IO_CAPABILITIES_REPLY);
6264 }
6265 
6266 uint8_t gap_ssp_io_capabilities_negative(const bd_addr_t addr){
6267     return gap_set_auth_flag_and_run(addr, SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
6268 }
6269 #endif
6270 
6271 #ifdef ENABLE_CLASSIC_PAIRING_OOB
6272 /**
6273  * @brief Report Remote OOB Data
6274  * @param bd_addr
6275  * @param c_192 Simple Pairing Hash C derived from P-192 public key
6276  * @param r_192 Simple Pairing Randomizer derived from P-192 public key
6277  * @param c_256 Simple Pairing Hash C derived from P-256 public key
6278  * @param r_256 Simple Pairing Randomizer derived from P-256 public key
6279  */
6280 uint8_t gap_ssp_remote_oob_data(const bd_addr_t addr, const uint8_t * c_192, const uint8_t * r_192, const uint8_t * c_256, const uint8_t * r_256){
6281     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6282     if (connection == NULL) {
6283         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6284     }
6285     connection->classic_oob_c_192 = c_192;
6286     connection->classic_oob_r_192 = r_192;
6287     connection->classic_oob_c_256 = c_256;
6288     connection->classic_oob_r_256 = r_256;
6289     return ERROR_CODE_SUCCESS;
6290 }
6291 /**
6292  * @brief Generate new OOB data
6293  * @note OOB data will be provided in GAP_EVENT_LOCAL_OOB_DATA and be used in future pairing procedures
6294  */
6295 void gap_ssp_generate_oob_data(void){
6296     hci_stack->classic_read_local_oob_data = true;
6297     hci_run();
6298 }
6299 
6300 #endif
6301 
6302 /**
6303  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
6304  * @param inquiry_mode see bluetooth_defines.h
6305  */
6306 void hci_set_inquiry_mode(inquiry_mode_t inquiry_mode){
6307     hci_stack->inquiry_mode = inquiry_mode;
6308 }
6309 
6310 /**
6311  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
6312  */
6313 void hci_set_sco_voice_setting(uint16_t voice_setting){
6314     hci_stack->sco_voice_setting = voice_setting;
6315 }
6316 
6317 /**
6318  * @brief Get SCO Voice Setting
6319  * @return current voice setting
6320  */
6321 uint16_t hci_get_sco_voice_setting(void){
6322     return hci_stack->sco_voice_setting;
6323 }
6324 
6325 static int hci_have_usb_transport(void){
6326     if (!hci_stack->hci_transport) return 0;
6327     const char * transport_name = hci_stack->hci_transport->name;
6328     if (!transport_name) return 0;
6329     return (transport_name[0] == 'H') && (transport_name[1] == '2');
6330 }
6331 
6332 /** @brief Get SCO packet length for current SCO Voice setting
6333  *  @note  Using SCO packets of the exact length is required for USB transfer
6334  *  @return Length of SCO packets in bytes (not audio frames)
6335  */
6336 int hci_get_sco_packet_length(void){
6337     int sco_packet_length = 0;
6338 
6339 #ifdef ENABLE_SCO_OVER_HCI
6340     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6341     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6342 
6343     if (hci_have_usb_transport()){
6344         // see Core Spec for H2 USB Transfer.
6345         // 3 byte SCO header + 24 bytes per connection
6346         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
6347         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
6348     } else {
6349         // 3 byte SCO header + SCO packet size over the air (60 bytes)
6350         sco_packet_length = 3 + 60 * multiplier;
6351         // assert that it still fits inside an SCO buffer
6352         if (sco_packet_length > hci_stack->sco_data_packet_length){
6353             sco_packet_length = 3 + 60;
6354         }
6355     }
6356 #endif
6357 
6358 #ifdef HAVE_SCO_TRANSPORT
6359     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6360     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6361     sco_packet_length = 3 + 60 * multiplier;
6362 #endif
6363     return sco_packet_length;
6364 }
6365 
6366 /**
6367 * @brief Sets the master/slave policy
6368 * @param policy (0: attempt to become master, 1: let connecting device decide)
6369 */
6370 void hci_set_master_slave_policy(uint8_t policy){
6371     hci_stack->master_slave_policy = policy;
6372 }
6373 
6374 #endif
6375 
6376 HCI_STATE hci_get_state(void){
6377     return hci_stack->state;
6378 }
6379 
6380 #ifdef ENABLE_CLASSIC
6381 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
6382     hci_stack->gap_classic_accept_callback = accept_callback;
6383 }
6384 #endif
6385 
6386 /**
6387  * @brief Set callback for Bluetooth Hardware Error
6388  */
6389 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
6390     hci_stack->hardware_error_callback = fn;
6391 }
6392 
6393 void hci_disconnect_all(void){
6394     btstack_linked_list_iterator_t it;
6395     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6396     while (btstack_linked_list_iterator_has_next(&it)){
6397         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6398         if (con->state == SENT_DISCONNECT) continue;
6399         con->state = SEND_DISCONNECT;
6400     }
6401     hci_run();
6402 }
6403 
6404 uint16_t hci_get_manufacturer(void){
6405     return hci_stack->manufacturer;
6406 }
6407 
6408 #ifdef ENABLE_BLE
6409 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
6410     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
6411     if (!hci_con) return NULL;
6412     return &hci_con->sm_connection;
6413 }
6414 
6415 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
6416 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
6417 #endif
6418 
6419 int gap_encryption_key_size(hci_con_handle_t con_handle){
6420     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6421     if (hci_connection == NULL) return 0;
6422     if (hci_is_le_connection(hci_connection)){
6423 #ifdef ENABLE_BLE
6424         sm_connection_t * sm_conn = &hci_connection->sm_connection;
6425         if (sm_conn->sm_connection_encrypted) {
6426             return sm_conn->sm_actual_encryption_key_size;
6427         }
6428 #endif
6429     } else {
6430 #ifdef ENABLE_CLASSIC
6431         if ((hci_connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED)){
6432             return hci_connection->encryption_key_size;
6433         }
6434 #endif
6435     }
6436     return 0;
6437 }
6438 
6439 int gap_authenticated(hci_con_handle_t con_handle){
6440     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6441     if (hci_connection == NULL) return 0;
6442 
6443     switch (hci_connection->address_type){
6444 #ifdef ENABLE_BLE
6445         case BD_ADDR_TYPE_LE_PUBLIC:
6446         case BD_ADDR_TYPE_LE_RANDOM:
6447             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6448             return hci_connection->sm_connection.sm_connection_authenticated;
6449 #endif
6450 #ifdef ENABLE_CLASSIC
6451         case BD_ADDR_TYPE_SCO:
6452         case BD_ADDR_TYPE_ACL:
6453             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
6454 #endif
6455         default:
6456             return 0;
6457     }
6458 }
6459 
6460 int gap_secure_connection(hci_con_handle_t con_handle){
6461     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6462     if (hci_connection == NULL) return 0;
6463 
6464     switch (hci_connection->address_type){
6465 #ifdef ENABLE_BLE
6466         case BD_ADDR_TYPE_LE_PUBLIC:
6467         case BD_ADDR_TYPE_LE_RANDOM:
6468             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6469             return hci_connection->sm_connection.sm_connection_sc;
6470 #endif
6471 #ifdef ENABLE_CLASSIC
6472         case BD_ADDR_TYPE_SCO:
6473         case BD_ADDR_TYPE_ACL:
6474             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
6475 #endif
6476         default:
6477             return 0;
6478     }
6479 }
6480 
6481 bool gap_bonded(hci_con_handle_t con_handle){
6482 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6483 	if (hci_connection == NULL) return 0;
6484 
6485 #ifdef ENABLE_CLASSIC
6486 	link_key_t link_key;
6487 	link_key_type_t link_key_type;
6488 #endif
6489 	switch (hci_connection->address_type){
6490 #ifdef ENABLE_BLE
6491 		case BD_ADDR_TYPE_LE_PUBLIC:
6492 		case BD_ADDR_TYPE_LE_RANDOM:
6493 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6494 #endif
6495 #ifdef ENABLE_CLASSIC
6496 		case BD_ADDR_TYPE_SCO:
6497 		case BD_ADDR_TYPE_ACL:
6498 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6499 #endif
6500 		default:
6501 			return false;
6502 	}
6503 }
6504 
6505 #ifdef ENABLE_BLE
6506 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6507     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6508     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6509     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6510     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6511     return sm_conn->sm_connection_authorization_state;
6512 }
6513 #endif
6514 
6515 #ifdef ENABLE_CLASSIC
6516 uint8_t gap_sniff_mode_enter(hci_con_handle_t con_handle, uint16_t sniff_min_interval, uint16_t sniff_max_interval, uint16_t sniff_attempt, uint16_t sniff_timeout){
6517     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6518     if (!conn) return GAP_CONNECTION_INVALID;
6519     conn->sniff_min_interval = sniff_min_interval;
6520     conn->sniff_max_interval = sniff_max_interval;
6521     conn->sniff_attempt = sniff_attempt;
6522     conn->sniff_timeout = sniff_timeout;
6523     hci_run();
6524     return 0;
6525 }
6526 
6527 /**
6528  * @brief Exit Sniff mode
6529  * @param con_handle
6530  @ @return 0 if ok
6531  */
6532 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6533     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6534     if (!conn) return GAP_CONNECTION_INVALID;
6535     conn->sniff_min_interval = 0xffff;
6536     hci_run();
6537     return 0;
6538 }
6539 
6540 uint8_t gap_sniff_subrating_configure(hci_con_handle_t con_handle, uint16_t max_latency, uint16_t min_remote_timeout, uint16_t min_local_timeout){
6541     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6542     if (!conn) return GAP_CONNECTION_INVALID;
6543     conn->sniff_subrating_max_latency = max_latency;
6544     conn->sniff_subrating_min_remote_timeout = min_remote_timeout;
6545     conn->sniff_subrating_min_local_timeout = min_local_timeout;
6546     hci_run();
6547     return ERROR_CODE_SUCCESS;
6548 }
6549 
6550 uint8_t gap_qos_set(hci_con_handle_t con_handle, hci_service_type_t service_type, uint32_t token_rate, uint32_t peak_bandwidth, uint32_t latency, uint32_t delay_variation){
6551     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6552     if (!conn) return GAP_CONNECTION_INVALID;
6553     conn->qos_service_type = service_type;
6554     conn->qos_token_rate = token_rate;
6555     conn->qos_peak_bandwidth = peak_bandwidth;
6556     conn->qos_latency = latency;
6557     conn->qos_delay_variation = delay_variation;
6558     hci_run();
6559     return ERROR_CODE_SUCCESS;
6560 }
6561 
6562 void gap_set_page_scan_activity(uint16_t page_scan_interval, uint16_t page_scan_window){
6563     hci_stack->new_page_scan_interval = page_scan_interval;
6564     hci_stack->new_page_scan_window = page_scan_window;
6565     hci_run();
6566 }
6567 
6568 void gap_set_page_scan_type(page_scan_type_t page_scan_type){
6569     hci_stack->new_page_scan_type = (uint8_t) page_scan_type;
6570     hci_run();
6571 }
6572 
6573 #endif
6574 
6575 void hci_halting_defer(void){
6576     if (hci_stack->state != HCI_STATE_HALTING) return;
6577     switch (hci_stack->substate){
6578         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6579         case HCI_HALTING_CLOSE:
6580             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6581             break;
6582         default:
6583             break;
6584     }
6585 }
6586 
6587 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6588 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6589     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6590     if (le_device_db_index >= le_device_db_max_count()) return;
6591     uint8_t offset = le_device_db_index >> 3;
6592     uint8_t mask = 1 << (le_device_db_index & 7);
6593     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6594     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6595     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6596         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6597     }
6598 }
6599 
6600 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6601 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6602 	if (le_device_db_index >= le_device_db_max_count()) return;
6603 	uint8_t offset = le_device_db_index >> 3;
6604 	uint8_t mask = 1 << (le_device_db_index & 7);
6605 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6606 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6607 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6608 	}
6609 }
6610 
6611 uint8_t gap_load_resolving_list_from_le_device_db(void){
6612 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6613 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6614 	}
6615 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6616 		// restart le resolving list update
6617 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6618 	}
6619 	return ERROR_CODE_SUCCESS;
6620 }
6621 #endif
6622 
6623 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6624 void hci_setup_test_connections_fuzz(void){
6625     hci_connection_t * conn;
6626 
6627     // default address: 66:55:44:33:00:01
6628     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6629 
6630     // setup Controller info
6631     hci_stack->num_cmd_packets = 255;
6632     hci_stack->acl_packets_total_num = 255;
6633 
6634     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6635     addr[5] = 0x01;
6636     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6637     conn->con_handle = addr[5];
6638     conn->role  = HCI_ROLE_SLAVE;
6639     conn->state = RECEIVED_CONNECTION_REQUEST;
6640     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6641 
6642     // setup incoming Classic SCO connection with con handle 0x0002
6643     addr[5] = 0x02;
6644     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6645     conn->con_handle = addr[5];
6646     conn->role  = HCI_ROLE_SLAVE;
6647     conn->state = RECEIVED_CONNECTION_REQUEST;
6648     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6649 
6650     // setup ready Classic ACL connection with con handle 0x0003
6651     addr[5] = 0x03;
6652     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6653     conn->con_handle = addr[5];
6654     conn->role  = HCI_ROLE_SLAVE;
6655     conn->state = OPEN;
6656     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6657 
6658     // setup ready Classic SCO connection with con handle 0x0004
6659     addr[5] = 0x04;
6660     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6661     conn->con_handle = addr[5];
6662     conn->role  = HCI_ROLE_SLAVE;
6663     conn->state = OPEN;
6664     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6665 
6666     // setup ready LE ACL connection with con handle 0x005 and public address
6667     addr[5] = 0x05;
6668     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6669     conn->con_handle = addr[5];
6670     conn->role  = HCI_ROLE_SLAVE;
6671     conn->state = OPEN;
6672     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6673     conn->sm_connection.sm_connection_encrypted = 1;
6674 }
6675 
6676 void hci_free_connections_fuzz(void){
6677     btstack_linked_list_iterator_t it;
6678     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6679     while (btstack_linked_list_iterator_has_next(&it)){
6680         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6681         btstack_linked_list_iterator_remove(&it);
6682         btstack_memory_hci_connection_free(con);
6683     }
6684 }
6685 void hci_simulate_working_fuzz(void){
6686     hci_init_done();
6687     hci_stack->num_cmd_packets = 255;
6688 }
6689 #endif
6690